{-
(c) The GRASP/AQUA Project, Glasgow University, 1992-1998

Renaming of expressions

Basically dependency analysis.

Handles @Match@, @GRHSs@, @HsExpr@, and @Qualifier@ datatypes.  In
general, all of these functions return a renamed thing, and a set of
free variables.
-}

{-# LANGUAGE CPP #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE ViewPatterns #-}

{-# OPTIONS_GHC -Wno-incomplete-record-updates #-}
{-# OPTIONS_GHC -Wno-incomplete-uni-patterns   #-}

module GHC.Rename.Expr (
        rnLExpr, rnExpr, rnStmts
   ) where

#include "HsVersions.h"

import GHC.Prelude

import GHC.Rename.Bind ( rnLocalBindsAndThen, rnLocalValBindsLHS, rnLocalValBindsRHS
                        , rnMatchGroup, rnGRHS, makeMiniFixityEnv)
import GHC.Hs
import GHC.Tc.Utils.Env ( isBrackStage )
import GHC.Tc.Utils.Monad
import GHC.Unit.Module ( getModule )
import GHC.Rename.Env
import GHC.Rename.Fixity
import GHC.Rename.Utils ( HsDocContext(..), bindLocalNamesFV, checkDupNames
                        , bindLocalNames
                        , mapMaybeFvRn, mapFvRn
                        , warnUnusedLocalBinds, typeAppErr
                        , checkUnusedRecordWildcard )
import GHC.Rename.Unbound ( reportUnboundName )
import GHC.Rename.Splice  ( rnBracket, rnSpliceExpr, checkThLocalName )
import GHC.Rename.HsType
import GHC.Rename.Pat
import GHC.Driver.Session
import GHC.Builtin.Names

import GHC.Types.Basic
import GHC.Types.Name
import GHC.Types.Name.Set
import GHC.Types.Name.Reader
import GHC.Types.Unique.Set
import Data.List
import Data.Maybe (isJust, isNothing)
import GHC.Utils.Misc
import GHC.Data.List.SetOps ( removeDups )
import GHC.Utils.Error
import GHC.Utils.Outputable as Outputable
import GHC.Types.SrcLoc
import GHC.Data.FastString
import Control.Monad
import GHC.Builtin.Types ( nilDataConName )
import qualified GHC.LanguageExtensions as LangExt

import Control.Arrow (first)
import Data.Ord
import Data.Array
import qualified Data.List.NonEmpty as NE

{-
************************************************************************
*                                                                      *
\subsubsection{Expressions}
*                                                                      *
************************************************************************
-}

rnExprs :: [LHsExpr GhcPs] -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs :: [LHsExpr GhcPs] -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs [LHsExpr GhcPs]
ls = [LHsExpr GhcPs] -> FreeVars -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs' [LHsExpr GhcPs]
ls FreeVars
forall a. UniqSet a
emptyUniqSet
 where
  rnExprs' :: [LHsExpr GhcPs] -> FreeVars -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs' [] FreeVars
acc = ([LHsExpr GhcRn], FreeVars) -> RnM ([LHsExpr GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([], FreeVars
acc)
  rnExprs' (LHsExpr GhcPs
expr:[LHsExpr GhcPs]
exprs) FreeVars
acc =
   do { (LHsExpr GhcRn
expr', FreeVars
fvExpr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
        -- Now we do a "seq" on the free vars because typically it's small
        -- or empty, especially in very long lists of constants
      ; let  acc' :: FreeVars
acc' = FreeVars
acc FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvExpr
      ; ([LHsExpr GhcRn]
exprs', FreeVars
fvExprs) <- FreeVars
acc' FreeVars
-> RnM ([LHsExpr GhcRn], FreeVars)
-> RnM ([LHsExpr GhcRn], FreeVars)
`seq` [LHsExpr GhcPs] -> FreeVars -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs' [LHsExpr GhcPs]
exprs FreeVars
acc'
      ; ([LHsExpr GhcRn], FreeVars) -> RnM ([LHsExpr GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn
expr'LHsExpr GhcRn -> [LHsExpr GhcRn] -> [LHsExpr GhcRn]
forall a. a -> [a] -> [a]
:[LHsExpr GhcRn]
exprs', FreeVars
fvExprs) }

-- Variables. We look up the variable and return the resulting name.

rnLExpr :: LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr :: LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr = (HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars))
-> LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
forall a b c. (a -> TcM (b, c)) -> Located a -> TcM (Located b, c)
wrapLocFstM HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnExpr

rnExpr :: HsExpr GhcPs -> RnM (HsExpr GhcRn, FreeVars)

finishHsVar :: Located Name -> RnM (HsExpr GhcRn, FreeVars)
-- Separated from rnExpr because it's also used
-- when renaming infix expressions
finishHsVar :: Located Name -> TcM (HsExpr GhcRn, FreeVars)
finishHsVar (L SrcSpan
l Name
name)
 = do { Module
this_mod <- IOEnv (Env TcGblEnv TcLclEnv) Module
forall (m :: * -> *). HasModule m => m Module
getModule
      ; Bool
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when (Module -> Name -> Bool
nameIsLocalOrFrom Module
this_mod Name
name) (IOEnv (Env TcGblEnv TcLclEnv) ()
 -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$
        Name -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkThLocalName Name
name
      ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XVar GhcRn -> Located (IdP GhcRn) -> HsExpr GhcRn
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar GhcRn
noExtField (SrcSpan -> Name -> Located Name
forall l e. l -> e -> GenLocated l e
L SrcSpan
l Name
name), Name -> FreeVars
unitFV Name
name) }

rnUnboundVar :: RdrName -> RnM (HsExpr GhcRn, FreeVars)
rnUnboundVar :: RdrName -> TcM (HsExpr GhcRn, FreeVars)
rnUnboundVar RdrName
v
 = do { if RdrName -> Bool
isUnqual RdrName
v
        then -- Treat this as a "hole"
             -- Do not fail right now; instead, return HsUnboundVar
             -- and let the type checker report the error
             (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XUnboundVar GhcRn -> OccName -> HsExpr GhcRn
forall p. XUnboundVar p -> OccName -> HsExpr p
HsUnboundVar NoExtField
XUnboundVar GhcRn
noExtField (RdrName -> OccName
rdrNameOcc RdrName
v), FreeVars
emptyFVs)

        else -- Fail immediately (qualified name)
             do { Name
n <- RdrName -> RnM Name
reportUnboundName RdrName
v
                ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XVar GhcRn -> Located (IdP GhcRn) -> HsExpr GhcRn
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar GhcRn
noExtField (Name -> Located Name
forall e. e -> Located e
noLoc Name
n), FreeVars
emptyFVs) } }

rnExpr :: HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnExpr (HsVar XVar GhcPs
_ (L SrcSpan
l IdP GhcPs
v))
  = do { Bool
opt_DuplicateRecordFields <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.DuplicateRecordFields
       ; Maybe (Either Name [Name])
mb_name <- Bool -> RdrName -> RnM (Maybe (Either Name [Name]))
lookupOccRn_overloaded Bool
opt_DuplicateRecordFields RdrName
IdP GhcPs
v
       ; DynFlags
dflags <- IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
       ; case Maybe (Either Name [Name])
mb_name of {
           Maybe (Either Name [Name])
Nothing -> RdrName -> TcM (HsExpr GhcRn, FreeVars)
rnUnboundVar RdrName
IdP GhcPs
v ;
           Just (Left Name
name)
              | Name
name Name -> Name -> Bool
forall a. Eq a => a -> a -> Bool
== Name
nilDataConName -- Treat [] as an ExplicitList, so that
                                       -- OverloadedLists works correctly
                                       -- Note [Empty lists] in GHC.Hs.Expr
              , Extension -> DynFlags -> Bool
xopt Extension
LangExt.OverloadedLists DynFlags
dflags
              -> HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnExpr (XExplicitList GhcPs
-> Maybe (SyntaxExpr GhcPs) -> [LHsExpr GhcPs] -> HsExpr GhcPs
forall p.
XExplicitList p -> Maybe (SyntaxExpr p) -> [LHsExpr p] -> HsExpr p
ExplicitList NoExtField
XExplicitList GhcPs
noExtField Maybe (SyntaxExpr GhcPs)
forall a. Maybe a
Nothing [])

              | Bool
otherwise
              -> Located Name -> TcM (HsExpr GhcRn, FreeVars)
finishHsVar (SrcSpan -> Name -> Located Name
forall l e. l -> e -> GenLocated l e
L SrcSpan
l Name
name) ;
            Just (Right [Name
s]) ->
              (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( XRecFld GhcRn -> AmbiguousFieldOcc GhcRn -> HsExpr GhcRn
forall p. XRecFld p -> AmbiguousFieldOcc p -> HsExpr p
HsRecFld NoExtField
XRecFld GhcRn
noExtField (XUnambiguous GhcRn -> Located RdrName -> AmbiguousFieldOcc GhcRn
forall pass.
XUnambiguous pass -> Located RdrName -> AmbiguousFieldOcc pass
Unambiguous Name
XUnambiguous GhcRn
s (SrcSpan -> RdrName -> Located RdrName
forall l e. l -> e -> GenLocated l e
L SrcSpan
l RdrName
IdP GhcPs
v) ), Name -> FreeVars
unitFV Name
s) ;
           Just (Right fs :: [Name]
fs@(Name
_:Name
_:[Name]
_)) ->
              (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( XRecFld GhcRn -> AmbiguousFieldOcc GhcRn -> HsExpr GhcRn
forall p. XRecFld p -> AmbiguousFieldOcc p -> HsExpr p
HsRecFld NoExtField
XRecFld GhcRn
noExtField (XAmbiguous GhcRn -> Located RdrName -> AmbiguousFieldOcc GhcRn
forall pass.
XAmbiguous pass -> Located RdrName -> AmbiguousFieldOcc pass
Ambiguous NoExtField
XAmbiguous GhcRn
noExtField (SrcSpan -> RdrName -> Located RdrName
forall l e. l -> e -> GenLocated l e
L SrcSpan
l RdrName
IdP GhcPs
v))
                     , [Name] -> FreeVars
mkFVs [Name]
fs);
           Just (Right [])         -> String -> TcM (HsExpr GhcRn, FreeVars)
forall a. String -> a
panic String
"runExpr/HsVar" } }

rnExpr (HsIPVar XIPVar GhcPs
x HsIPName
v)
  = (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XIPVar GhcRn -> HsIPName -> HsExpr GhcRn
forall p. XIPVar p -> HsIPName -> HsExpr p
HsIPVar XIPVar GhcPs
XIPVar GhcRn
x HsIPName
v, FreeVars
emptyFVs)

rnExpr (HsUnboundVar XUnboundVar GhcPs
x OccName
v)
  = (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XUnboundVar GhcRn -> OccName -> HsExpr GhcRn
forall p. XUnboundVar p -> OccName -> HsExpr p
HsUnboundVar XUnboundVar GhcPs
XUnboundVar GhcRn
x OccName
v, FreeVars
emptyFVs)

rnExpr (HsOverLabel XOverLabel GhcPs
x Maybe (IdP GhcPs)
_ FastString
v)
  = do { Bool
rebindable_on <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.RebindableSyntax
       ; if Bool
rebindable_on
         then do { Name
fromLabel <- RdrName -> RnM Name
lookupOccRn (FastString -> RdrName
mkVarUnqual (String -> FastString
fsLit String
"fromLabel"))
                 ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XOverLabel GhcRn -> Maybe (IdP GhcRn) -> FastString -> HsExpr GhcRn
forall p. XOverLabel p -> Maybe (IdP p) -> FastString -> HsExpr p
HsOverLabel XOverLabel GhcPs
XOverLabel GhcRn
x (Name -> Maybe Name
forall a. a -> Maybe a
Just Name
fromLabel) FastString
v, Name -> FreeVars
unitFV Name
fromLabel) }
         else (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XOverLabel GhcRn -> Maybe (IdP GhcRn) -> FastString -> HsExpr GhcRn
forall p. XOverLabel p -> Maybe (IdP p) -> FastString -> HsExpr p
HsOverLabel XOverLabel GhcPs
XOverLabel GhcRn
x Maybe (IdP GhcRn)
forall a. Maybe a
Nothing FastString
v, FreeVars
emptyFVs) }

rnExpr (HsLit XLitE GhcPs
x lit :: HsLit GhcPs
lit@(HsString XHsString GhcPs
src FastString
s))
  = do { Bool
opt_OverloadedStrings <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedStrings
       ; if Bool
opt_OverloadedStrings then
            HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnExpr (XOverLitE GhcPs -> HsOverLit GhcPs -> HsExpr GhcPs
forall p. XOverLitE p -> HsOverLit p -> HsExpr p
HsOverLit XLitE GhcPs
XOverLitE GhcPs
x (SourceText -> FastString -> HsOverLit GhcPs
mkHsIsString SourceText
XHsString GhcPs
src FastString
s))
         else do {
            ; HsLit GhcPs -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall p. HsLit p -> IOEnv (Env TcGblEnv TcLclEnv) ()
rnLit HsLit GhcPs
lit
            ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XLitE GhcRn -> HsLit GhcRn -> HsExpr GhcRn
forall p. XLitE p -> HsLit p -> HsExpr p
HsLit XLitE GhcPs
XLitE GhcRn
x (HsLit GhcPs -> HsLit GhcRn
forall (p1 :: Pass) (p2 :: Pass).
HsLit (GhcPass p1) -> HsLit (GhcPass p2)
convertLit HsLit GhcPs
lit), FreeVars
emptyFVs) } }

rnExpr (HsLit XLitE GhcPs
x HsLit GhcPs
lit)
  = do { HsLit GhcPs -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall p. HsLit p -> IOEnv (Env TcGblEnv TcLclEnv) ()
rnLit HsLit GhcPs
lit
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XLitE GhcRn -> HsLit GhcRn -> HsExpr GhcRn
forall p. XLitE p -> HsLit p -> HsExpr p
HsLit XLitE GhcPs
XLitE GhcRn
x(HsLit GhcPs -> HsLit GhcRn
forall (p1 :: Pass) (p2 :: Pass).
HsLit (GhcPass p1) -> HsLit (GhcPass p2)
convertLit HsLit GhcPs
lit), FreeVars
emptyFVs) }

rnExpr (HsOverLit XOverLitE GhcPs
x HsOverLit GhcPs
lit)
  = do { ((HsOverLit GhcRn
lit', Maybe (HsExpr GhcRn)
mb_neg), FreeVars
fvs) <- HsOverLit GhcPs
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
forall t.
HsOverLit t
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
rnOverLit HsOverLit GhcPs
lit -- See Note [Negative zero]
       ; case Maybe (HsExpr GhcRn)
mb_neg of
              Maybe (HsExpr GhcRn)
Nothing -> (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XOverLitE GhcRn -> HsOverLit GhcRn -> HsExpr GhcRn
forall p. XOverLitE p -> HsOverLit p -> HsExpr p
HsOverLit XOverLitE GhcPs
XOverLitE GhcRn
x HsOverLit GhcRn
lit', FreeVars
fvs)
              Just HsExpr GhcRn
neg -> (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XApp GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XApp p -> LHsExpr p -> LHsExpr p -> HsExpr p
HsApp XApp GhcRn
XOverLitE GhcPs
x (HsExpr GhcRn -> LHsExpr GhcRn
forall e. e -> Located e
noLoc HsExpr GhcRn
neg) (HsExpr GhcRn -> LHsExpr GhcRn
forall e. e -> Located e
noLoc (XOverLitE GhcRn -> HsOverLit GhcRn -> HsExpr GhcRn
forall p. XOverLitE p -> HsOverLit p -> HsExpr p
HsOverLit XOverLitE GhcPs
XOverLitE GhcRn
x HsOverLit GhcRn
lit'))
                                 , FreeVars
fvs ) }

rnExpr (HsApp XApp GhcPs
x LHsExpr GhcPs
fun LHsExpr GhcPs
arg)
  = do { (LHsExpr GhcRn
fun',FreeVars
fvFun) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
fun
       ; (LHsExpr GhcRn
arg',FreeVars
fvArg) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
arg
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XApp GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XApp p -> LHsExpr p -> LHsExpr p -> HsExpr p
HsApp XApp GhcPs
XApp GhcRn
x LHsExpr GhcRn
fun' LHsExpr GhcRn
arg', FreeVars
fvFun FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvArg) }

rnExpr (HsAppType XAppTypeE GhcPs
x LHsExpr GhcPs
fun LHsWcType (NoGhcTc GhcPs)
arg)
  = do { Bool
type_app <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.TypeApplications
       ; Bool
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
unless Bool
type_app (IOEnv (Env TcGblEnv TcLclEnv) ()
 -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$ MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$ String -> LHsType GhcPs -> MsgDoc
typeAppErr String
"type" (LHsType GhcPs -> MsgDoc) -> LHsType GhcPs -> MsgDoc
forall a b. (a -> b) -> a -> b
$ HsWildCardBndrs GhcPs (LHsType GhcPs) -> LHsType GhcPs
forall pass thing. HsWildCardBndrs pass thing -> thing
hswc_body HsWildCardBndrs GhcPs (LHsType GhcPs)
LHsWcType (NoGhcTc GhcPs)
arg
       ; (LHsExpr GhcRn
fun',FreeVars
fvFun) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
fun
       ; (LHsWcType GhcRn
arg',FreeVars
fvArg) <- HsDocContext
-> HsWildCardBndrs GhcPs (LHsType GhcPs)
-> RnM (LHsWcType GhcRn, FreeVars)
rnHsWcType HsDocContext
HsTypeCtx HsWildCardBndrs GhcPs (LHsType GhcPs)
LHsWcType (NoGhcTc GhcPs)
arg
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XAppTypeE GhcRn
-> LHsExpr GhcRn -> LHsWcType (NoGhcTc GhcRn) -> HsExpr GhcRn
forall p.
XAppTypeE p -> LHsExpr p -> LHsWcType (NoGhcTc p) -> HsExpr p
HsAppType XAppTypeE GhcPs
XAppTypeE GhcRn
x LHsExpr GhcRn
fun' LHsWcType GhcRn
LHsWcType (NoGhcTc GhcRn)
arg', FreeVars
fvFun FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvArg) }

rnExpr (OpApp XOpApp GhcPs
_ LHsExpr GhcPs
e1 LHsExpr GhcPs
op LHsExpr GhcPs
e2)
  = do  { (LHsExpr GhcRn
e1', FreeVars
fv_e1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
e1
        ; (LHsExpr GhcRn
e2', FreeVars
fv_e2) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
e2
        ; (LHsExpr GhcRn
op', FreeVars
fv_op) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
op

        -- Deal with fixity
        -- When renaming code synthesised from "deriving" declarations
        -- we used to avoid fixity stuff, but we can't easily tell any
        -- more, so I've removed the test.  Adding HsPars in GHC.Tc.Deriv.Generate
        -- should prevent bad things happening.
        ; Fixity
fixity <- case LHsExpr GhcRn
op' of
              L SrcSpan
_ (HsVar XVar GhcRn
_ (L SrcSpan
_ IdP GhcRn
n)) -> Name -> IOEnv (Env TcGblEnv TcLclEnv) Fixity
lookupFixityRn Name
IdP GhcRn
n
              L SrcSpan
_ (HsRecFld XRecFld GhcRn
_ AmbiguousFieldOcc GhcRn
f)    -> AmbiguousFieldOcc GhcRn -> IOEnv (Env TcGblEnv TcLclEnv) Fixity
lookupFieldFixityRn AmbiguousFieldOcc GhcRn
f
              LHsExpr GhcRn
_ -> Fixity -> IOEnv (Env TcGblEnv TcLclEnv) Fixity
forall (m :: * -> *) a. Monad m => a -> m a
return (SourceText -> Int -> FixityDirection -> Fixity
Fixity SourceText
NoSourceText Int
minPrecedence FixityDirection
InfixL)
                   -- c.f. lookupFixity for unbound

        ; Bool
lexical_negation <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.LexicalNegation
        ; let negation_handling :: NegationHandling
negation_handling | Bool
lexical_negation = NegationHandling
KeepNegationIntact
                                | Bool
otherwise = NegationHandling
ReassociateNegation
        ; HsExpr GhcRn
final_e <- NegationHandling
-> LHsExpr GhcRn
-> LHsExpr GhcRn
-> Fixity
-> LHsExpr GhcRn
-> RnM (HsExpr GhcRn)
mkOpAppRn NegationHandling
negation_handling LHsExpr GhcRn
e1' LHsExpr GhcRn
op' Fixity
fixity LHsExpr GhcRn
e2'
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (HsExpr GhcRn
final_e, FreeVars
fv_e1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_op FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_e2) }

rnExpr (NegApp XNegApp GhcPs
_ LHsExpr GhcPs
e SyntaxExpr GhcPs
_)
  = do { (LHsExpr GhcRn
e', FreeVars
fv_e)         <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
e
       ; (SyntaxExprRn
neg_name, FreeVars
fv_neg) <- Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
negateName
       ; HsExpr GhcRn
final_e            <- LHsExpr GhcRn -> SyntaxExpr GhcRn -> RnM (HsExpr GhcRn)
forall (id :: Pass).
LHsExpr (GhcPass id)
-> SyntaxExpr (GhcPass id) -> RnM (HsExpr (GhcPass id))
mkNegAppRn LHsExpr GhcRn
e' SyntaxExpr GhcRn
SyntaxExprRn
neg_name
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (HsExpr GhcRn
final_e, FreeVars
fv_e FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_neg) }

------------------------------------------
-- Template Haskell extensions
rnExpr e :: HsExpr GhcPs
e@(HsBracket XBracket GhcPs
_ HsBracket GhcPs
br_body) = HsExpr GhcPs -> HsBracket GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnBracket HsExpr GhcPs
e HsBracket GhcPs
br_body

rnExpr (HsSpliceE XSpliceE GhcPs
_ HsSplice GhcPs
splice) = HsSplice GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSpliceExpr HsSplice GhcPs
splice

---------------------------------------------
--      Sections
-- See Note [Parsing sections] in GHC.Parser
rnExpr (HsPar XPar GhcPs
x (L SrcSpan
loc (section :: HsExpr GhcPs
section@(SectionL {}))))
  = do  { (HsExpr GhcRn
section', FreeVars
fvs) <- HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSection HsExpr GhcPs
section
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XPar GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XPar p -> LHsExpr p -> HsExpr p
HsPar XPar GhcPs
XPar GhcRn
x (SrcSpan -> HsExpr GhcRn -> LHsExpr GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc HsExpr GhcRn
section'), FreeVars
fvs) }

rnExpr (HsPar XPar GhcPs
x (L SrcSpan
loc (section :: HsExpr GhcPs
section@(SectionR {}))))
  = do  { (HsExpr GhcRn
section', FreeVars
fvs) <- HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSection HsExpr GhcPs
section
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XPar GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XPar p -> LHsExpr p -> HsExpr p
HsPar XPar GhcPs
XPar GhcRn
x (SrcSpan -> HsExpr GhcRn -> LHsExpr GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc HsExpr GhcRn
section'), FreeVars
fvs) }

rnExpr (HsPar XPar GhcPs
x LHsExpr GhcPs
e)
  = do  { (LHsExpr GhcRn
e', FreeVars
fvs_e) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
e
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XPar GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XPar p -> LHsExpr p -> HsExpr p
HsPar XPar GhcPs
XPar GhcRn
x LHsExpr GhcRn
e', FreeVars
fvs_e) }

rnExpr expr :: HsExpr GhcPs
expr@(SectionL {})
  = do  { MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (HsExpr GhcPs -> MsgDoc
sectionErr HsExpr GhcPs
expr); HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSection HsExpr GhcPs
expr }
rnExpr expr :: HsExpr GhcPs
expr@(SectionR {})
  = do  { MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (HsExpr GhcPs -> MsgDoc
sectionErr HsExpr GhcPs
expr); HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSection HsExpr GhcPs
expr }

---------------------------------------------
rnExpr (HsPragE XPragE GhcPs
x HsPragE GhcPs
prag LHsExpr GhcPs
expr)
  = do { (LHsExpr GhcRn
expr', FreeVars
fvs_expr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XPragE GhcRn -> HsPragE GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XPragE p -> HsPragE p -> LHsExpr p -> HsExpr p
HsPragE XPragE GhcPs
XPragE GhcRn
x (HsPragE GhcPs -> HsPragE GhcRn
rn_prag HsPragE GhcPs
prag) LHsExpr GhcRn
expr', FreeVars
fvs_expr) }
  where
    rn_prag :: HsPragE GhcPs -> HsPragE GhcRn
    rn_prag :: HsPragE GhcPs -> HsPragE GhcRn
rn_prag (HsPragSCC XSCC GhcPs
x1 SourceText
src StringLiteral
ann) = XSCC GhcRn -> SourceText -> StringLiteral -> HsPragE GhcRn
forall p. XSCC p -> SourceText -> StringLiteral -> HsPragE p
HsPragSCC XSCC GhcPs
XSCC GhcRn
x1 SourceText
src StringLiteral
ann
    rn_prag (HsPragTick XTickPragma GhcPs
x1 SourceText
src (StringLiteral, (Int, Int), (Int, Int))
info ((SourceText, SourceText), (SourceText, SourceText))
srcInfo) = XTickPragma GhcRn
-> SourceText
-> (StringLiteral, (Int, Int), (Int, Int))
-> ((SourceText, SourceText), (SourceText, SourceText))
-> HsPragE GhcRn
forall p.
XTickPragma p
-> SourceText
-> (StringLiteral, (Int, Int), (Int, Int))
-> ((SourceText, SourceText), (SourceText, SourceText))
-> HsPragE p
HsPragTick XTickPragma GhcPs
XTickPragma GhcRn
x1 SourceText
src (StringLiteral, (Int, Int), (Int, Int))
info ((SourceText, SourceText), (SourceText, SourceText))
srcInfo

rnExpr (HsLam XLam GhcPs
x MatchGroup GhcPs (LHsExpr GhcPs)
matches)
  = do { (MatchGroup GhcRn (LHsExpr GhcRn)
matches', FreeVars
fvMatch) <- HsMatchContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsExpr GhcPs)
-> RnM (MatchGroup GhcRn (LHsExpr GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
LambdaExpr LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr MatchGroup GhcPs (LHsExpr GhcPs)
matches
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XLam GhcRn -> MatchGroup GhcRn (LHsExpr GhcRn) -> HsExpr GhcRn
forall p. XLam p -> MatchGroup p (LHsExpr p) -> HsExpr p
HsLam XLam GhcPs
XLam GhcRn
x MatchGroup GhcRn (LHsExpr GhcRn)
matches', FreeVars
fvMatch) }

rnExpr (HsLamCase XLamCase GhcPs
x MatchGroup GhcPs (LHsExpr GhcPs)
matches)
  = do { (MatchGroup GhcRn (LHsExpr GhcRn)
matches', FreeVars
fvs_ms) <- HsMatchContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsExpr GhcPs)
-> RnM (MatchGroup GhcRn (LHsExpr GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
CaseAlt LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr MatchGroup GhcPs (LHsExpr GhcPs)
matches
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XLamCase GhcRn -> MatchGroup GhcRn (LHsExpr GhcRn) -> HsExpr GhcRn
forall p. XLamCase p -> MatchGroup p (LHsExpr p) -> HsExpr p
HsLamCase XLamCase GhcPs
XLamCase GhcRn
x MatchGroup GhcRn (LHsExpr GhcRn)
matches', FreeVars
fvs_ms) }

rnExpr (HsCase XCase GhcPs
x LHsExpr GhcPs
expr MatchGroup GhcPs (LHsExpr GhcPs)
matches)
  = do { (LHsExpr GhcRn
new_expr, FreeVars
e_fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
       ; (MatchGroup GhcRn (LHsExpr GhcRn)
new_matches, FreeVars
ms_fvs) <- HsMatchContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsExpr GhcPs)
-> RnM (MatchGroup GhcRn (LHsExpr GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
CaseAlt LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr MatchGroup GhcPs (LHsExpr GhcPs)
matches
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCase GhcRn
-> LHsExpr GhcRn
-> MatchGroup GhcRn (LHsExpr GhcRn)
-> HsExpr GhcRn
forall p.
XCase p -> LHsExpr p -> MatchGroup p (LHsExpr p) -> HsExpr p
HsCase XCase GhcPs
XCase GhcRn
x LHsExpr GhcRn
new_expr MatchGroup GhcRn (LHsExpr GhcRn)
new_matches, FreeVars
e_fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
ms_fvs) }

rnExpr (HsLet XLet GhcPs
x (L SrcSpan
l HsLocalBinds GhcPs
binds) LHsExpr GhcPs
expr)
  = HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn -> FreeVars -> TcM (HsExpr GhcRn, FreeVars))
-> TcM (HsExpr GhcRn, FreeVars)
forall result.
HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn -> FreeVars -> RnM (result, FreeVars))
-> RnM (result, FreeVars)
rnLocalBindsAndThen HsLocalBinds GhcPs
binds ((HsLocalBinds GhcRn -> FreeVars -> TcM (HsExpr GhcRn, FreeVars))
 -> TcM (HsExpr GhcRn, FreeVars))
-> (HsLocalBinds GhcRn -> FreeVars -> TcM (HsExpr GhcRn, FreeVars))
-> TcM (HsExpr GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$ \HsLocalBinds GhcRn
binds' FreeVars
_ -> do
      { (LHsExpr GhcRn
expr',FreeVars
fvExpr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
      ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XLet GhcRn -> LHsLocalBinds GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XLet p -> LHsLocalBinds p -> LHsExpr p -> HsExpr p
HsLet XLet GhcPs
XLet GhcRn
x (SrcSpan -> HsLocalBinds GhcRn -> LHsLocalBinds GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
l HsLocalBinds GhcRn
binds') LHsExpr GhcRn
expr', FreeVars
fvExpr) }

rnExpr (HsDo XDo GhcPs
x HsStmtContext GhcRn
do_or_lc (L SrcSpan
l [ExprLStmt GhcPs]
stmts))
  = do  { (([ExprLStmt GhcRn]
stmts', ()
_), FreeVars
fvs) <-
           HsStmtContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> (HsStmtContext GhcRn
    -> [(ExprLStmt GhcRn, FreeVars)]
    -> RnM ([ExprLStmt GhcRn], FreeVars))
-> [ExprLStmt GhcPs]
-> ([Name] -> RnM ((), FreeVars))
-> RnM (([ExprLStmt GhcRn], ()), FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> (HsStmtContext GhcRn
    -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
    -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmtsWithPostProcessing HsStmtContext GhcRn
do_or_lc LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr
             HsStmtContext GhcRn
-> [(ExprLStmt GhcRn, FreeVars)]
-> RnM ([ExprLStmt GhcRn], FreeVars)
postProcessStmtsForApplicativeDo [ExprLStmt GhcPs]
stmts
             (\ [Name]
_ -> ((), FreeVars) -> RnM ((), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((), FreeVars
emptyFVs))
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( XDo GhcRn
-> HsStmtContext GhcRn -> Located [ExprLStmt GhcRn] -> HsExpr GhcRn
forall p.
XDo p -> HsStmtContext GhcRn -> Located [ExprLStmt p] -> HsExpr p
HsDo XDo GhcPs
XDo GhcRn
x HsStmtContext GhcRn
do_or_lc (SrcSpan -> [ExprLStmt GhcRn] -> Located [ExprLStmt GhcRn]
forall l e. l -> e -> GenLocated l e
L SrcSpan
l [ExprLStmt GhcRn]
stmts'), FreeVars
fvs ) }

rnExpr (ExplicitList XExplicitList GhcPs
x Maybe (SyntaxExpr GhcPs)
_  [LHsExpr GhcPs]
exps)
  = do  { Bool
opt_OverloadedLists <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedLists
        ; ([LHsExpr GhcRn]
exps', FreeVars
fvs) <- [LHsExpr GhcPs] -> RnM ([LHsExpr GhcRn], FreeVars)
rnExprs [LHsExpr GhcPs]
exps
        ; if Bool
opt_OverloadedLists
           then do {
            ; (SyntaxExprRn
from_list_n_name, FreeVars
fvs') <- Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
fromListNName
            ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XExplicitList GhcRn
-> Maybe (SyntaxExpr GhcRn) -> [LHsExpr GhcRn] -> HsExpr GhcRn
forall p.
XExplicitList p -> Maybe (SyntaxExpr p) -> [LHsExpr p] -> HsExpr p
ExplicitList XExplicitList GhcPs
XExplicitList GhcRn
x (SyntaxExprRn -> Maybe SyntaxExprRn
forall a. a -> Maybe a
Just SyntaxExprRn
from_list_n_name) [LHsExpr GhcRn]
exps'
                     , FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs') }
           else
            (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return  (XExplicitList GhcRn
-> Maybe (SyntaxExpr GhcRn) -> [LHsExpr GhcRn] -> HsExpr GhcRn
forall p.
XExplicitList p -> Maybe (SyntaxExpr p) -> [LHsExpr p] -> HsExpr p
ExplicitList XExplicitList GhcPs
XExplicitList GhcRn
x Maybe (SyntaxExpr GhcRn)
forall a. Maybe a
Nothing [LHsExpr GhcRn]
exps', FreeVars
fvs) }

rnExpr (ExplicitTuple XExplicitTuple GhcPs
x [LHsTupArg GhcPs]
tup_args Boxity
boxity)
  = do { [LHsTupArg GhcPs] -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkTupleSection [LHsTupArg GhcPs]
tup_args
       ; Int -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkTupSize ([LHsTupArg GhcPs] -> Int
forall (t :: * -> *) a. Foldable t => t a -> Int
length [LHsTupArg GhcPs]
tup_args)
       ; ([GenLocated SrcSpan (HsTupArg GhcRn)]
tup_args', [FreeVars]
fvs) <- (LHsTupArg GhcPs
 -> IOEnv
      (Env TcGblEnv TcLclEnv)
      (GenLocated SrcSpan (HsTupArg GhcRn), FreeVars))
-> [LHsTupArg GhcPs]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([GenLocated SrcSpan (HsTupArg GhcRn)], [FreeVars])
forall (m :: * -> *) a b c.
Applicative m =>
(a -> m (b, c)) -> [a] -> m ([b], [c])
mapAndUnzipM LHsTupArg GhcPs
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated SrcSpan (HsTupArg GhcRn), FreeVars)
forall {l}.
GenLocated l (HsTupArg GhcPs)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated l (HsTupArg GhcRn), FreeVars)
rnTupArg [LHsTupArg GhcPs]
tup_args
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XExplicitTuple GhcRn
-> [GenLocated SrcSpan (HsTupArg GhcRn)] -> Boxity -> HsExpr GhcRn
forall p. XExplicitTuple p -> [LHsTupArg p] -> Boxity -> HsExpr p
ExplicitTuple XExplicitTuple GhcPs
XExplicitTuple GhcRn
x [GenLocated SrcSpan (HsTupArg GhcRn)]
tup_args' Boxity
boxity, [FreeVars] -> FreeVars
plusFVs [FreeVars]
fvs) }
  where
    rnTupArg :: GenLocated l (HsTupArg GhcPs)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated l (HsTupArg GhcRn), FreeVars)
rnTupArg (L l
l (Present XPresent GhcPs
x LHsExpr GhcPs
e)) = do { (LHsExpr GhcRn
e',FreeVars
fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
e
                                      ; (GenLocated l (HsTupArg GhcRn), FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated l (HsTupArg GhcRn), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (l -> HsTupArg GhcRn -> GenLocated l (HsTupArg GhcRn)
forall l e. l -> e -> GenLocated l e
L l
l (XPresent GhcRn -> LHsExpr GhcRn -> HsTupArg GhcRn
forall id. XPresent id -> LHsExpr id -> HsTupArg id
Present XPresent GhcPs
XPresent GhcRn
x LHsExpr GhcRn
e'), FreeVars
fvs) }
    rnTupArg (L l
l (Missing XMissing GhcPs
_)) = (GenLocated l (HsTupArg GhcRn), FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated l (HsTupArg GhcRn), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (l -> HsTupArg GhcRn -> GenLocated l (HsTupArg GhcRn)
forall l e. l -> e -> GenLocated l e
L l
l (XMissing GhcRn -> HsTupArg GhcRn
forall id. XMissing id -> HsTupArg id
Missing NoExtField
XMissing GhcRn
noExtField)
                                        , FreeVars
emptyFVs)

rnExpr (ExplicitSum XExplicitSum GhcPs
x Int
alt Int
arity LHsExpr GhcPs
expr)
  = do { (LHsExpr GhcRn
expr', FreeVars
fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XExplicitSum GhcRn -> Int -> Int -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XExplicitSum p -> Int -> Int -> LHsExpr p -> HsExpr p
ExplicitSum XExplicitSum GhcPs
XExplicitSum GhcRn
x Int
alt Int
arity LHsExpr GhcRn
expr', FreeVars
fvs) }

rnExpr (RecordCon { rcon_con_name :: forall p. HsExpr p -> Located (IdP p)
rcon_con_name = GenLocated SrcSpan (IdP GhcPs)
con_id
                  , rcon_flds :: forall p. HsExpr p -> HsRecordBinds p
rcon_flds = rec_binds :: HsRecordBinds GhcPs
rec_binds@(HsRecFields { rec_dotdot :: forall p arg. HsRecFields p arg -> Maybe (Located Int)
rec_dotdot = Maybe (Located Int)
dd }) })
  = do { con_lname :: Located Name
con_lname@(L SrcSpan
_ Name
con_name) <- Located RdrName -> RnM (Located Name)
lookupLocatedOccRn Located RdrName
GenLocated SrcSpan (IdP GhcPs)
con_id
       ; ([LHsRecField GhcRn (LHsExpr GhcPs)]
flds, FreeVars
fvs)   <- HsRecFieldContext
-> (SrcSpan -> RdrName -> HsExpr GhcPs)
-> HsRecordBinds GhcPs
-> RnM ([LHsRecField GhcRn (LHsExpr GhcPs)], FreeVars)
forall arg.
HsRecFieldContext
-> (SrcSpan -> RdrName -> arg)
-> HsRecFields GhcPs (Located arg)
-> RnM ([LHsRecField GhcRn (Located arg)], FreeVars)
rnHsRecFields (Name -> HsRecFieldContext
HsRecFieldCon Name
con_name) SrcSpan -> RdrName -> HsExpr GhcPs
forall {p}. (XVar p ~ NoExtField) => SrcSpan -> IdP p -> HsExpr p
mk_hs_var HsRecordBinds GhcPs
rec_binds
       ; ([GenLocated SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn))]
flds', [FreeVars]
fvss) <- (LHsRecField GhcRn (LHsExpr GhcPs)
 -> IOEnv
      (Env TcGblEnv TcLclEnv)
      (GenLocated SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn)),
       FreeVars))
-> [LHsRecField GhcRn (LHsExpr GhcPs)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([GenLocated
         SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn))],
      [FreeVars])
forall (m :: * -> *) a b c.
Applicative m =>
(a -> m (b, c)) -> [a] -> m ([b], [c])
mapAndUnzipM LHsRecField GhcRn (LHsExpr GhcPs)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn)),
      FreeVars)
forall {l} {id}.
GenLocated l (HsRecField' id (LHsExpr GhcPs))
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated l (HsRecField' id (LHsExpr GhcRn)), FreeVars)
rn_field [LHsRecField GhcRn (LHsExpr GhcPs)]
flds
       ; let rec_binds' :: HsRecFields GhcRn (LHsExpr GhcRn)
rec_binds' = HsRecFields :: forall p arg.
[LHsRecField p arg] -> Maybe (Located Int) -> HsRecFields p arg
HsRecFields { rec_flds :: [GenLocated SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn))]
rec_flds = [GenLocated SrcSpan (HsRecField' (FieldOcc GhcRn) (LHsExpr GhcRn))]
flds', rec_dotdot :: Maybe (Located Int)
rec_dotdot = Maybe (Located Int)
dd }
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (RecordCon :: forall p.
XRecordCon p -> Located (IdP p) -> HsRecordBinds p -> HsExpr p
RecordCon { rcon_ext :: XRecordCon GhcRn
rcon_ext = NoExtField
XRecordCon GhcRn
noExtField
                           , rcon_con_name :: Located (IdP GhcRn)
rcon_con_name = Located Name
Located (IdP GhcRn)
con_lname, rcon_flds :: HsRecFields GhcRn (LHsExpr GhcRn)
rcon_flds = HsRecFields GhcRn (LHsExpr GhcRn)
rec_binds' }
                , FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` [FreeVars] -> FreeVars
plusFVs [FreeVars]
fvss FreeVars -> Name -> FreeVars
`addOneFV` Name
con_name) }
  where
    mk_hs_var :: SrcSpan -> IdP p -> HsExpr p
mk_hs_var SrcSpan
l IdP p
n = XVar p -> Located (IdP p) -> HsExpr p
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar p
noExtField (SrcSpan -> IdP p -> Located (IdP p)
forall l e. l -> e -> GenLocated l e
L SrcSpan
l IdP p
n)
    rn_field :: GenLocated l (HsRecField' id (LHsExpr GhcPs))
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated l (HsRecField' id (LHsExpr GhcRn)), FreeVars)
rn_field (L l
l HsRecField' id (LHsExpr GhcPs)
fld) = do { (LHsExpr GhcRn
arg', FreeVars
fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr (HsRecField' id (LHsExpr GhcPs) -> LHsExpr GhcPs
forall id arg. HsRecField' id arg -> arg
hsRecFieldArg HsRecField' id (LHsExpr GhcPs)
fld)
                            ; (GenLocated l (HsRecField' id (LHsExpr GhcRn)), FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated l (HsRecField' id (LHsExpr GhcRn)), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (l
-> HsRecField' id (LHsExpr GhcRn)
-> GenLocated l (HsRecField' id (LHsExpr GhcRn))
forall l e. l -> e -> GenLocated l e
L l
l (HsRecField' id (LHsExpr GhcPs)
fld { hsRecFieldArg :: LHsExpr GhcRn
hsRecFieldArg = LHsExpr GhcRn
arg' }), FreeVars
fvs) }

rnExpr (RecordUpd { rupd_expr :: forall p. HsExpr p -> LHsExpr p
rupd_expr = LHsExpr GhcPs
expr, rupd_flds :: forall p. HsExpr p -> [LHsRecUpdField p]
rupd_flds = [LHsRecUpdField GhcPs]
rbinds })
  = do  { (LHsExpr GhcRn
expr', FreeVars
fvExpr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
        ; ([LHsRecUpdField GhcRn]
rbinds', FreeVars
fvRbinds) <- [LHsRecUpdField GhcPs] -> RnM ([LHsRecUpdField GhcRn], FreeVars)
rnHsRecUpdFields [LHsRecUpdField GhcPs]
rbinds
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (RecordUpd :: forall p.
XRecordUpd p -> LHsExpr p -> [LHsRecUpdField p] -> HsExpr p
RecordUpd { rupd_ext :: XRecordUpd GhcRn
rupd_ext = NoExtField
XRecordUpd GhcRn
noExtField, rupd_expr :: LHsExpr GhcRn
rupd_expr = LHsExpr GhcRn
expr'
                            , rupd_flds :: [LHsRecUpdField GhcRn]
rupd_flds = [LHsRecUpdField GhcRn]
rbinds' }
                 , FreeVars
fvExpr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvRbinds) }

rnExpr (ExprWithTySig XExprWithTySig GhcPs
_ LHsExpr GhcPs
expr LHsSigWcType (NoGhcTc GhcPs)
pty)
  = do  { (LHsSigWcType GhcRn
pty', FreeVars
fvTy)    <- HsDocContext
-> LHsSigWcType GhcPs -> RnM (LHsSigWcType GhcRn, FreeVars)
rnHsSigWcType HsDocContext
ExprWithTySigCtx LHsSigWcType GhcPs
LHsSigWcType (NoGhcTc GhcPs)
pty
        ; (LHsExpr GhcRn
expr', FreeVars
fvExpr) <- [Name]
-> RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
forall a. [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
bindSigTyVarsFV (LHsSigWcType GhcRn -> [Name]
hsWcScopedTvs LHsSigWcType GhcRn
pty') (RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars))
-> RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$
                             LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XExprWithTySig GhcRn
-> LHsExpr GhcRn -> LHsSigWcType (NoGhcTc GhcRn) -> HsExpr GhcRn
forall p.
XExprWithTySig p
-> LHsExpr p -> LHsSigWcType (NoGhcTc p) -> HsExpr p
ExprWithTySig NoExtField
XExprWithTySig GhcRn
noExtField LHsExpr GhcRn
expr' LHsSigWcType GhcRn
LHsSigWcType (NoGhcTc GhcRn)
pty', FreeVars
fvExpr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvTy) }
rnExpr (HsIf XIf GhcPs
_ LHsExpr GhcPs
p LHsExpr GhcPs
b1 LHsExpr GhcPs
b2)
  = do { (LHsExpr GhcRn
p', FreeVars
fvP) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
p
       ; (LHsExpr GhcRn
b1', FreeVars
fvB1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
b1
       ; (LHsExpr GhcRn
b2', FreeVars
fvB2) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
b2
       ; Maybe (Located Name)
mifteName <- RnM (Maybe (Located Name))
lookupReboundIf
       ; let subFVs :: FreeVars
subFVs = [FreeVars] -> FreeVars
plusFVs [FreeVars
fvP, FreeVars
fvB1, FreeVars
fvB2]
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars))
-> (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$ case Maybe (Located Name)
mifteName of
           -- RS is off, we keep an 'HsIf' node around
           Maybe (Located Name)
Nothing ->
             (XIf GhcRn
-> LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XIf p -> LHsExpr p -> LHsExpr p -> LHsExpr p -> HsExpr p
HsIf NoExtField
XIf GhcRn
noExtField  LHsExpr GhcRn
p' LHsExpr GhcRn
b1' LHsExpr GhcRn
b2', FreeVars
subFVs)
           -- See Note [Rebindable syntax and HsExpansion].
           Just Located Name
ifteName ->
             let ifteExpr :: HsExpr GhcRn
ifteExpr = Located Name
-> LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
rebindIf Located Name
ifteName LHsExpr GhcRn
p' LHsExpr GhcRn
b1' LHsExpr GhcRn
b2'
             in (HsExpr GhcRn
ifteExpr, [FreeVars] -> FreeVars
plusFVs [Name -> FreeVars
unitFV (Located Name -> Name
forall l e. GenLocated l e -> e
unLoc Located Name
ifteName), FreeVars
subFVs])
       }
rnExpr (HsMultiIf XMultiIf GhcPs
x [LGRHS GhcPs (LHsExpr GhcPs)]
alts)
  = do { ([LGRHS GhcRn (LHsExpr GhcRn)]
alts', FreeVars
fvs) <- (LGRHS GhcPs (LHsExpr GhcPs)
 -> RnM (LGRHS GhcRn (LHsExpr GhcRn), FreeVars))
-> [LGRHS GhcPs (LHsExpr GhcPs)]
-> RnM ([LGRHS GhcRn (LHsExpr GhcRn)], FreeVars)
forall a b. (a -> RnM (b, FreeVars)) -> [a] -> RnM ([b], FreeVars)
mapFvRn (HsMatchContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> LGRHS GhcPs (LHsExpr GhcPs)
-> RnM (LGRHS GhcRn (LHsExpr GhcRn), FreeVars)
forall (body :: * -> *).
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LGRHS GhcPs (Located (body GhcPs))
-> RnM (LGRHS GhcRn (Located (body GhcRn)), FreeVars)
rnGRHS HsMatchContext GhcRn
forall p. HsMatchContext p
IfAlt LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr) [LGRHS GhcPs (LHsExpr GhcPs)]
alts
       -- ; return (HsMultiIf ty alts', fvs) }
       ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XMultiIf GhcRn -> [LGRHS GhcRn (LHsExpr GhcRn)] -> HsExpr GhcRn
forall p. XMultiIf p -> [LGRHS p (LHsExpr p)] -> HsExpr p
HsMultiIf XMultiIf GhcPs
XMultiIf GhcRn
x [LGRHS GhcRn (LHsExpr GhcRn)]
alts', FreeVars
fvs) }

rnExpr (ArithSeq XArithSeq GhcPs
x Maybe (SyntaxExpr GhcPs)
_ ArithSeqInfo GhcPs
seq)
  = do { Bool
opt_OverloadedLists <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedLists
       ; (ArithSeqInfo GhcRn
new_seq, FreeVars
fvs) <- ArithSeqInfo GhcPs -> RnM (ArithSeqInfo GhcRn, FreeVars)
rnArithSeq ArithSeqInfo GhcPs
seq
       ; if Bool
opt_OverloadedLists
           then do {
            ; (SyntaxExprRn
from_list_name, FreeVars
fvs') <- Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
fromListName
            ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XArithSeq GhcRn
-> Maybe (SyntaxExpr GhcRn) -> ArithSeqInfo GhcRn -> HsExpr GhcRn
forall p.
XArithSeq p -> Maybe (SyntaxExpr p) -> ArithSeqInfo p -> HsExpr p
ArithSeq XArithSeq GhcPs
XArithSeq GhcRn
x (SyntaxExprRn -> Maybe SyntaxExprRn
forall a. a -> Maybe a
Just SyntaxExprRn
from_list_name) ArithSeqInfo GhcRn
new_seq
                     , FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs') }
           else
            (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XArithSeq GhcRn
-> Maybe (SyntaxExpr GhcRn) -> ArithSeqInfo GhcRn -> HsExpr GhcRn
forall p.
XArithSeq p -> Maybe (SyntaxExpr p) -> ArithSeqInfo p -> HsExpr p
ArithSeq XArithSeq GhcPs
XArithSeq GhcRn
x Maybe (SyntaxExpr GhcRn)
forall a. Maybe a
Nothing ArithSeqInfo GhcRn
new_seq, FreeVars
fvs) }

{-
************************************************************************
*                                                                      *
        Static values
*                                                                      *
************************************************************************

For the static form we check that it is not used in splices.
We also collect the free variables of the term which come from
this module. See Note [Grand plan for static forms] in GHC.Iface.Tidy.StaticPtrTable.
-}

rnExpr e :: HsExpr GhcPs
e@(HsStatic XStatic GhcPs
_ LHsExpr GhcPs
expr) = do
    -- Normally, you wouldn't be able to construct a static expression without
    -- first enabling -XStaticPointers in the first place, since that extension
    -- is what makes the parser treat `static` as a keyword. But this is not a
    -- sufficient safeguard, as one can construct static expressions by another
    -- mechanism: Template Haskell (see #14204). To ensure that GHC is
    -- absolutely prepared to cope with static forms, we check for
    -- -XStaticPointers here as well.
    Extension
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall gbl lcl. Extension -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()
unlessXOptM Extension
LangExt.StaticPointers (IOEnv (Env TcGblEnv TcLclEnv) ()
 -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$
      MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$ MsgDoc -> Int -> MsgDoc -> MsgDoc
hang (String -> MsgDoc
text String
"Illegal static expression:" MsgDoc -> MsgDoc -> MsgDoc
<+> HsExpr GhcPs -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr HsExpr GhcPs
e)
                  Int
2 (String -> MsgDoc
text String
"Use StaticPointers to enable this extension")
    (LHsExpr GhcRn
expr',FreeVars
fvExpr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
    ThStage
stage <- TcM ThStage
getStage
    case ThStage
stage of
      Splice SpliceType
_ -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall a b. (a -> b) -> a -> b
$ [MsgDoc] -> MsgDoc
sep
             [ String -> MsgDoc
text String
"static forms cannot be used in splices:"
             , Int -> MsgDoc -> MsgDoc
nest Int
2 (MsgDoc -> MsgDoc) -> MsgDoc -> MsgDoc
forall a b. (a -> b) -> a -> b
$ HsExpr GhcPs -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr HsExpr GhcPs
e
             ]
      ThStage
_ -> () -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
    Module
mod <- IOEnv (Env TcGblEnv TcLclEnv) Module
forall (m :: * -> *). HasModule m => m Module
getModule
    let fvExpr' :: FreeVars
fvExpr' = (Name -> Bool) -> FreeVars -> FreeVars
filterNameSet (Module -> Name -> Bool
nameIsLocalOrFrom Module
mod) FreeVars
fvExpr
    (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XStatic GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XStatic p -> LHsExpr p -> HsExpr p
HsStatic FreeVars
XStatic GhcRn
fvExpr' LHsExpr GhcRn
expr', FreeVars
fvExpr)

{-
************************************************************************
*                                                                      *
        Arrow notation
*                                                                      *
************************************************************************
-}

rnExpr (HsProc XProc GhcPs
x LPat GhcPs
pat LHsCmdTop GhcPs
body)
  = TcM (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall a. TcM a -> TcM a
newArrowScope (TcM (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars))
-> TcM (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$
    HsMatchContext GhcRn
-> LPat GhcPs
-> (LPat GhcRn -> TcM (HsExpr GhcRn, FreeVars))
-> TcM (HsExpr GhcRn, FreeVars)
forall a.
HsMatchContext GhcRn
-> LPat GhcPs
-> (LPat GhcRn -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnPat HsMatchContext GhcRn
forall p. HsMatchContext p
ProcExpr LPat GhcPs
pat ((LPat GhcRn -> TcM (HsExpr GhcRn, FreeVars))
 -> TcM (HsExpr GhcRn, FreeVars))
-> (LPat GhcRn -> TcM (HsExpr GhcRn, FreeVars))
-> TcM (HsExpr GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$ \ LPat GhcRn
pat' -> do
      { (LHsCmdTop GhcRn
body',FreeVars
fvBody) <- LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop LHsCmdTop GhcPs
body
      ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XProc GhcRn -> LPat GhcRn -> LHsCmdTop GhcRn -> HsExpr GhcRn
forall p. XProc p -> LPat p -> LHsCmdTop p -> HsExpr p
HsProc XProc GhcPs
XProc GhcRn
x LPat GhcRn
pat' LHsCmdTop GhcRn
body', FreeVars
fvBody) }

rnExpr HsExpr GhcPs
other = String -> MsgDoc -> TcM (HsExpr GhcRn, FreeVars)
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rnExpr: unexpected expression" (HsExpr GhcPs -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr HsExpr GhcPs
other)
        -- HsWrap

----------------------
-- See Note [Parsing sections] in GHC.Parser
rnSection :: HsExpr GhcPs -> RnM (HsExpr GhcRn, FreeVars)
rnSection :: HsExpr GhcPs -> TcM (HsExpr GhcRn, FreeVars)
rnSection section :: HsExpr GhcPs
section@(SectionR XSectionR GhcPs
x LHsExpr GhcPs
op LHsExpr GhcPs
expr)
  = do  { (LHsExpr GhcRn
op', FreeVars
fvs_op)     <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
op
        ; (LHsExpr GhcRn
expr', FreeVars
fvs_expr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
        ; FixityDirection
-> HsExpr GhcPs
-> LHsExpr GhcRn
-> LHsExpr GhcRn
-> IOEnv (Env TcGblEnv TcLclEnv) ()
checkSectionPrec FixityDirection
InfixR HsExpr GhcPs
section LHsExpr GhcRn
op' LHsExpr GhcRn
expr'
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XSectionR GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XSectionR p -> LHsExpr p -> LHsExpr p -> HsExpr p
SectionR XSectionR GhcPs
XSectionR GhcRn
x LHsExpr GhcRn
op' LHsExpr GhcRn
expr', FreeVars
fvs_op FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs_expr) }

rnSection section :: HsExpr GhcPs
section@(SectionL XSectionL GhcPs
x LHsExpr GhcPs
expr LHsExpr GhcPs
op)
  = do  { (LHsExpr GhcRn
expr', FreeVars
fvs_expr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
        ; (LHsExpr GhcRn
op', FreeVars
fvs_op)     <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
op
        ; FixityDirection
-> HsExpr GhcPs
-> LHsExpr GhcRn
-> LHsExpr GhcRn
-> IOEnv (Env TcGblEnv TcLclEnv) ()
checkSectionPrec FixityDirection
InfixL HsExpr GhcPs
section LHsExpr GhcRn
op' LHsExpr GhcRn
expr'
        ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XSectionL GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XSectionL p -> LHsExpr p -> LHsExpr p -> HsExpr p
SectionL XSectionL GhcPs
XSectionL GhcRn
x LHsExpr GhcRn
expr' LHsExpr GhcRn
op', FreeVars
fvs_op FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs_expr) }

rnSection HsExpr GhcPs
other = String -> MsgDoc -> TcM (HsExpr GhcRn, FreeVars)
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rnSection" (HsExpr GhcPs -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr HsExpr GhcPs
other)

{-
************************************************************************
*                                                                      *
        Arrow commands
*                                                                      *
************************************************************************
-}

rnCmdArgs :: [LHsCmdTop GhcPs] -> RnM ([LHsCmdTop GhcRn], FreeVars)
rnCmdArgs :: [LHsCmdTop GhcPs] -> RnM ([LHsCmdTop GhcRn], FreeVars)
rnCmdArgs [] = ([LHsCmdTop GhcRn], FreeVars) -> RnM ([LHsCmdTop GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([], FreeVars
emptyFVs)
rnCmdArgs (LHsCmdTop GhcPs
arg:[LHsCmdTop GhcPs]
args)
  = do { (LHsCmdTop GhcRn
arg',FreeVars
fvArg) <- LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop LHsCmdTop GhcPs
arg
       ; ([LHsCmdTop GhcRn]
args',FreeVars
fvArgs) <- [LHsCmdTop GhcPs] -> RnM ([LHsCmdTop GhcRn], FreeVars)
rnCmdArgs [LHsCmdTop GhcPs]
args
       ; ([LHsCmdTop GhcRn], FreeVars) -> RnM ([LHsCmdTop GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsCmdTop GhcRn
arg'LHsCmdTop GhcRn -> [LHsCmdTop GhcRn] -> [LHsCmdTop GhcRn]
forall a. a -> [a] -> [a]
:[LHsCmdTop GhcRn]
args', FreeVars
fvArg FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvArgs) }

rnCmdTop :: LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop :: LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop = (HsCmdTop GhcPs -> TcM (HsCmdTop GhcRn, FreeVars))
-> LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
forall a b c. (a -> TcM (b, c)) -> Located a -> TcM (Located b, c)
wrapLocFstM HsCmdTop GhcPs -> TcM (HsCmdTop GhcRn, FreeVars)
rnCmdTop'
 where
  rnCmdTop' :: HsCmdTop GhcPs -> TcM (HsCmdTop GhcRn, FreeVars)
rnCmdTop' (HsCmdTop XCmdTop GhcPs
_ LHsCmd GhcPs
cmd)
   = do { (LHsCmd GhcRn
cmd', FreeVars
fvCmd) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd LHsCmd GhcPs
cmd
        ; let cmd_names :: [Name]
cmd_names = [Name
arrAName, Name
composeAName, Name
firstAName] [Name] -> [Name] -> [Name]
forall a. [a] -> [a] -> [a]
++
                          FreeVars -> [Name]
nameSetElemsStable (HsCmd GhcRn -> FreeVars
methodNamesCmd (LHsCmd GhcRn -> HsCmd GhcRn
forall l e. GenLocated l e -> e
unLoc LHsCmd GhcRn
cmd'))
        -- Generate the rebindable syntax for the monad
        ; ([HsExpr GhcRn]
cmd_names', FreeVars
cmd_fvs) <- [Name] -> RnM ([HsExpr GhcRn], FreeVars)
lookupSyntaxNames [Name]
cmd_names

        ; (HsCmdTop GhcRn, FreeVars) -> TcM (HsCmdTop GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdTop GhcRn -> LHsCmd GhcRn -> HsCmdTop GhcRn
forall p. XCmdTop p -> LHsCmd p -> HsCmdTop p
HsCmdTop ([Name]
cmd_names [Name] -> [HsExpr GhcRn] -> [(Name, HsExpr GhcRn)]
forall a b. [a] -> [b] -> [(a, b)]
`zip` [HsExpr GhcRn]
cmd_names') LHsCmd GhcRn
cmd',
                  FreeVars
fvCmd FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
cmd_fvs) }

rnLCmd :: LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd :: LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd = (HsCmd GhcPs -> TcM (HsCmd GhcRn, FreeVars))
-> LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
forall a b c. (a -> TcM (b, c)) -> Located a -> TcM (Located b, c)
wrapLocFstM HsCmd GhcPs -> TcM (HsCmd GhcRn, FreeVars)
rnCmd

rnCmd :: HsCmd GhcPs -> RnM (HsCmd GhcRn, FreeVars)

rnCmd :: HsCmd GhcPs -> TcM (HsCmd GhcRn, FreeVars)
rnCmd (HsCmdArrApp XCmdArrApp GhcPs
x LHsExpr GhcPs
arrow LHsExpr GhcPs
arg HsArrAppType
ho Bool
rtl)
  = do { (LHsExpr GhcRn
arrow',FreeVars
fvArrow) <- RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
select_arrow_scope (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
arrow)
       ; (LHsExpr GhcRn
arg',FreeVars
fvArg) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
arg
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdArrApp GhcRn
-> LHsExpr GhcRn
-> LHsExpr GhcRn
-> HsArrAppType
-> Bool
-> HsCmd GhcRn
forall id.
XCmdArrApp id
-> LHsExpr id -> LHsExpr id -> HsArrAppType -> Bool -> HsCmd id
HsCmdArrApp XCmdArrApp GhcPs
XCmdArrApp GhcRn
x LHsExpr GhcRn
arrow' LHsExpr GhcRn
arg' HsArrAppType
ho Bool
rtl,
                 FreeVars
fvArrow FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvArg) }
  where
    select_arrow_scope :: RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
select_arrow_scope RnM (LHsExpr GhcRn, FreeVars)
tc = case HsArrAppType
ho of
        HsArrAppType
HsHigherOrderApp -> RnM (LHsExpr GhcRn, FreeVars)
tc
        HsArrAppType
HsFirstOrderApp  -> RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
forall a. TcM a -> TcM a
escapeArrowScope RnM (LHsExpr GhcRn, FreeVars)
tc
        -- See Note [Escaping the arrow scope] in GHC.Tc.Types
        -- Before renaming 'arrow', use the environment of the enclosing
        -- proc for the (-<) case.
        -- Local bindings, inside the enclosing proc, are not in scope
        -- inside 'arrow'.  In the higher-order case (-<<), they are.

-- infix form
rnCmd (HsCmdArrForm XCmdArrForm GhcPs
_ LHsExpr GhcPs
op LexicalFixity
_ (Just Fixity
_) [LHsCmdTop GhcPs
arg1, LHsCmdTop GhcPs
arg2])
  = do { (LHsExpr GhcRn
op',FreeVars
fv_op) <- RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
forall a. TcM a -> TcM a
escapeArrowScope (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
op)
       ; let L SrcSpan
_ (HsVar XVar GhcRn
_ (L SrcSpan
_ IdP GhcRn
op_name)) = LHsExpr GhcRn
op'
       ; (LHsCmdTop GhcRn
arg1',FreeVars
fv_arg1) <- LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop LHsCmdTop GhcPs
arg1
       ; (LHsCmdTop GhcRn
arg2',FreeVars
fv_arg2) <- LHsCmdTop GhcPs -> RnM (LHsCmdTop GhcRn, FreeVars)
rnCmdTop LHsCmdTop GhcPs
arg2
        -- Deal with fixity
       ; Fixity
fixity <- Name -> IOEnv (Env TcGblEnv TcLclEnv) Fixity
lookupFixityRn Name
IdP GhcRn
op_name
       ; HsCmd GhcRn
final_e <- LHsCmdTop GhcRn
-> LHsExpr GhcRn -> Fixity -> LHsCmdTop GhcRn -> RnM (HsCmd GhcRn)
mkOpFormRn LHsCmdTop GhcRn
arg1' LHsExpr GhcRn
op' Fixity
fixity LHsCmdTop GhcRn
arg2'
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (HsCmd GhcRn
final_e, FreeVars
fv_arg1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_op FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_arg2) }

rnCmd (HsCmdArrForm XCmdArrForm GhcPs
x LHsExpr GhcPs
op LexicalFixity
f Maybe Fixity
fixity [LHsCmdTop GhcPs]
cmds)
  = do { (LHsExpr GhcRn
op',FreeVars
fvOp) <- RnM (LHsExpr GhcRn, FreeVars) -> RnM (LHsExpr GhcRn, FreeVars)
forall a. TcM a -> TcM a
escapeArrowScope (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
op)
       ; ([LHsCmdTop GhcRn]
cmds',FreeVars
fvCmds) <- [LHsCmdTop GhcPs] -> RnM ([LHsCmdTop GhcRn], FreeVars)
rnCmdArgs [LHsCmdTop GhcPs]
cmds
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdArrForm GhcRn
-> LHsExpr GhcRn
-> LexicalFixity
-> Maybe Fixity
-> [LHsCmdTop GhcRn]
-> HsCmd GhcRn
forall id.
XCmdArrForm id
-> LHsExpr id
-> LexicalFixity
-> Maybe Fixity
-> [LHsCmdTop id]
-> HsCmd id
HsCmdArrForm XCmdArrForm GhcPs
XCmdArrForm GhcRn
x LHsExpr GhcRn
op' LexicalFixity
f Maybe Fixity
fixity [LHsCmdTop GhcRn]
cmds', FreeVars
fvOp FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvCmds) }

rnCmd (HsCmdApp XCmdApp GhcPs
x LHsCmd GhcPs
fun LHsExpr GhcPs
arg)
  = do { (LHsCmd GhcRn
fun',FreeVars
fvFun) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd  LHsCmd GhcPs
fun
       ; (LHsExpr GhcRn
arg',FreeVars
fvArg) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
arg
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdApp GhcRn -> LHsCmd GhcRn -> LHsExpr GhcRn -> HsCmd GhcRn
forall id. XCmdApp id -> LHsCmd id -> LHsExpr id -> HsCmd id
HsCmdApp XCmdApp GhcPs
XCmdApp GhcRn
x LHsCmd GhcRn
fun' LHsExpr GhcRn
arg', FreeVars
fvFun FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvArg) }

rnCmd (HsCmdLam XCmdLam GhcPs
x MatchGroup GhcPs (LHsCmd GhcPs)
matches)
  = do { (MatchGroup GhcRn (LHsCmd GhcRn)
matches', FreeVars
fvMatch) <- HsMatchContext GhcRn
-> (LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsCmd GhcPs)
-> RnM (MatchGroup GhcRn (LHsCmd GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
LambdaExpr LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd MatchGroup GhcPs (LHsCmd GhcPs)
matches
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdLam GhcRn -> MatchGroup GhcRn (LHsCmd GhcRn) -> HsCmd GhcRn
forall id. XCmdLam id -> MatchGroup id (LHsCmd id) -> HsCmd id
HsCmdLam XCmdLam GhcPs
XCmdLam GhcRn
x MatchGroup GhcRn (LHsCmd GhcRn)
matches', FreeVars
fvMatch) }

rnCmd (HsCmdPar XCmdPar GhcPs
x LHsCmd GhcPs
e)
  = do  { (LHsCmd GhcRn
e', FreeVars
fvs_e) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd LHsCmd GhcPs
e
        ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdPar GhcRn -> LHsCmd GhcRn -> HsCmd GhcRn
forall id. XCmdPar id -> LHsCmd id -> HsCmd id
HsCmdPar XCmdPar GhcPs
XCmdPar GhcRn
x LHsCmd GhcRn
e', FreeVars
fvs_e) }

rnCmd (HsCmdCase XCmdCase GhcPs
x LHsExpr GhcPs
expr MatchGroup GhcPs (LHsCmd GhcPs)
matches)
  = do { (LHsExpr GhcRn
new_expr, FreeVars
e_fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
       ; (MatchGroup GhcRn (LHsCmd GhcRn)
new_matches, FreeVars
ms_fvs) <- HsMatchContext GhcRn
-> (LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsCmd GhcPs)
-> RnM (MatchGroup GhcRn (LHsCmd GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
CaseAlt LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd MatchGroup GhcPs (LHsCmd GhcPs)
matches
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdCase GhcRn
-> LHsExpr GhcRn -> MatchGroup GhcRn (LHsCmd GhcRn) -> HsCmd GhcRn
forall id.
XCmdCase id -> LHsExpr id -> MatchGroup id (LHsCmd id) -> HsCmd id
HsCmdCase XCmdCase GhcPs
XCmdCase GhcRn
x LHsExpr GhcRn
new_expr MatchGroup GhcRn (LHsCmd GhcRn)
new_matches, FreeVars
e_fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
ms_fvs) }

rnCmd (HsCmdLamCase XCmdLamCase GhcPs
x MatchGroup GhcPs (LHsCmd GhcPs)
matches)
  = do { (MatchGroup GhcRn (LHsCmd GhcRn)
new_matches, FreeVars
ms_fvs) <- HsMatchContext GhcRn
-> (LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars))
-> MatchGroup GhcPs (LHsCmd GhcPs)
-> RnM (MatchGroup GhcRn (LHsCmd GhcRn), FreeVars)
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsMatchContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> MatchGroup GhcPs (Located (body GhcPs))
-> RnM (MatchGroup GhcRn (Located (body GhcRn)), FreeVars)
rnMatchGroup HsMatchContext GhcRn
forall p. HsMatchContext p
CaseAlt LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd MatchGroup GhcPs (LHsCmd GhcPs)
matches
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdLamCase GhcRn -> MatchGroup GhcRn (LHsCmd GhcRn) -> HsCmd GhcRn
forall id. XCmdLamCase id -> MatchGroup id (LHsCmd id) -> HsCmd id
HsCmdLamCase XCmdLamCase GhcPs
XCmdLamCase GhcRn
x MatchGroup GhcRn (LHsCmd GhcRn)
new_matches, FreeVars
ms_fvs) }

rnCmd (HsCmdIf XCmdIf GhcPs
x SyntaxExpr GhcPs
_ LHsExpr GhcPs
p LHsCmd GhcPs
b1 LHsCmd GhcPs
b2)
  = do { (LHsExpr GhcRn
p', FreeVars
fvP) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
p
       ; (LHsCmd GhcRn
b1', FreeVars
fvB1) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd LHsCmd GhcPs
b1
       ; (LHsCmd GhcRn
b2', FreeVars
fvB2) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd LHsCmd GhcPs
b2
       ; (SyntaxExprRn
mb_ite, FreeVars
fvITE) <- Bool -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupIfThenElse Bool
True
       ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdIf GhcRn
-> SyntaxExpr GhcRn
-> LHsExpr GhcRn
-> LHsCmd GhcRn
-> LHsCmd GhcRn
-> HsCmd GhcRn
forall id.
XCmdIf id
-> SyntaxExpr id
-> LHsExpr id
-> LHsCmd id
-> LHsCmd id
-> HsCmd id
HsCmdIf XCmdIf GhcPs
XCmdIf GhcRn
x SyntaxExpr GhcRn
SyntaxExprRn
mb_ite LHsExpr GhcRn
p' LHsCmd GhcRn
b1' LHsCmd GhcRn
b2', [FreeVars] -> FreeVars
plusFVs [FreeVars
fvITE, FreeVars
fvP, FreeVars
fvB1, FreeVars
fvB2])}

rnCmd (HsCmdLet XCmdLet GhcPs
x (L SrcSpan
l HsLocalBinds GhcPs
binds) LHsCmd GhcPs
cmd)
  = HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn -> FreeVars -> TcM (HsCmd GhcRn, FreeVars))
-> TcM (HsCmd GhcRn, FreeVars)
forall result.
HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn -> FreeVars -> RnM (result, FreeVars))
-> RnM (result, FreeVars)
rnLocalBindsAndThen HsLocalBinds GhcPs
binds ((HsLocalBinds GhcRn -> FreeVars -> TcM (HsCmd GhcRn, FreeVars))
 -> TcM (HsCmd GhcRn, FreeVars))
-> (HsLocalBinds GhcRn -> FreeVars -> TcM (HsCmd GhcRn, FreeVars))
-> TcM (HsCmd GhcRn, FreeVars)
forall a b. (a -> b) -> a -> b
$ \ HsLocalBinds GhcRn
binds' FreeVars
_ -> do
      { (LHsCmd GhcRn
cmd',FreeVars
fvExpr) <- LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd LHsCmd GhcPs
cmd
      ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XCmdLet GhcRn -> LHsLocalBinds GhcRn -> LHsCmd GhcRn -> HsCmd GhcRn
forall id. XCmdLet id -> LHsLocalBinds id -> LHsCmd id -> HsCmd id
HsCmdLet XCmdLet GhcPs
XCmdLet GhcRn
x (SrcSpan -> HsLocalBinds GhcRn -> LHsLocalBinds GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
l HsLocalBinds GhcRn
binds') LHsCmd GhcRn
cmd', FreeVars
fvExpr) }

rnCmd (HsCmdDo XCmdDo GhcPs
x (L SrcSpan
l [CmdLStmt GhcPs]
stmts))
  = do  { (([LStmt GhcRn (LHsCmd GhcRn)]
stmts', ()
_), FreeVars
fvs) <-
            HsStmtContext GhcRn
-> (LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars))
-> [CmdLStmt GhcPs]
-> ([Name] -> RnM ((), FreeVars))
-> RnM (([LStmt GhcRn (LHsCmd GhcRn)], ()), FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmts HsStmtContext GhcRn
forall p. HsStmtContext p
ArrowExpr LHsCmd GhcPs -> RnM (LHsCmd GhcRn, FreeVars)
rnLCmd [CmdLStmt GhcPs]
stmts (\ [Name]
_ -> ((), FreeVars) -> RnM ((), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((), FreeVars
emptyFVs))
        ; (HsCmd GhcRn, FreeVars) -> TcM (HsCmd GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( XCmdDo GhcRn -> Located [LStmt GhcRn (LHsCmd GhcRn)] -> HsCmd GhcRn
forall id. XCmdDo id -> Located [CmdLStmt id] -> HsCmd id
HsCmdDo XCmdDo GhcPs
XCmdDo GhcRn
x (SrcSpan
-> [LStmt GhcRn (LHsCmd GhcRn)]
-> Located [LStmt GhcRn (LHsCmd GhcRn)]
forall l e. l -> e -> GenLocated l e
L SrcSpan
l [LStmt GhcRn (LHsCmd GhcRn)]
stmts'), FreeVars
fvs ) }

---------------------------------------------------
type CmdNeeds = FreeVars        -- Only inhabitants are
                                --      appAName, choiceAName, loopAName

-- find what methods the Cmd needs (loop, choice, apply)
methodNamesLCmd :: LHsCmd GhcRn -> CmdNeeds
methodNamesLCmd :: LHsCmd GhcRn -> FreeVars
methodNamesLCmd = HsCmd GhcRn -> FreeVars
methodNamesCmd (HsCmd GhcRn -> FreeVars)
-> (LHsCmd GhcRn -> HsCmd GhcRn) -> LHsCmd GhcRn -> FreeVars
forall b c a. (b -> c) -> (a -> b) -> a -> c
. LHsCmd GhcRn -> HsCmd GhcRn
forall l e. GenLocated l e -> e
unLoc

methodNamesCmd :: HsCmd GhcRn -> CmdNeeds

methodNamesCmd :: HsCmd GhcRn -> FreeVars
methodNamesCmd (HsCmdArrApp XCmdArrApp GhcRn
_ LHsExpr GhcRn
_arrow LHsExpr GhcRn
_arg HsArrAppType
HsFirstOrderApp Bool
_rtl)
  = FreeVars
emptyFVs
methodNamesCmd (HsCmdArrApp XCmdArrApp GhcRn
_ LHsExpr GhcRn
_arrow LHsExpr GhcRn
_arg HsArrAppType
HsHigherOrderApp Bool
_rtl)
  = Name -> FreeVars
unitFV Name
appAName
methodNamesCmd (HsCmdArrForm {}) = FreeVars
emptyFVs

methodNamesCmd (HsCmdPar XCmdPar GhcRn
_ LHsCmd GhcRn
c) = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
c

methodNamesCmd (HsCmdIf XCmdIf GhcRn
_ SyntaxExpr GhcRn
_ LHsExpr GhcRn
_ LHsCmd GhcRn
c1 LHsCmd GhcRn
c2)
  = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
c1 FreeVars -> FreeVars -> FreeVars
`plusFV` LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
c2 FreeVars -> Name -> FreeVars
`addOneFV` Name
choiceAName

methodNamesCmd (HsCmdLet XCmdLet GhcRn
_ LHsLocalBinds GhcRn
_ LHsCmd GhcRn
c)          = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
c
methodNamesCmd (HsCmdDo XCmdDo GhcRn
_ (L SrcSpan
_ [LStmt GhcRn (LHsCmd GhcRn)]
stmts))   = [LStmt GhcRn (LHsCmd GhcRn)] -> FreeVars
methodNamesStmts [LStmt GhcRn (LHsCmd GhcRn)]
stmts
methodNamesCmd (HsCmdApp XCmdApp GhcRn
_ LHsCmd GhcRn
c LHsExpr GhcRn
_)          = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
c
methodNamesCmd (HsCmdLam XCmdLam GhcRn
_ MatchGroup GhcRn (LHsCmd GhcRn)
match)        = MatchGroup GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesMatch MatchGroup GhcRn (LHsCmd GhcRn)
match

methodNamesCmd (HsCmdCase XCmdCase GhcRn
_ LHsExpr GhcRn
_ MatchGroup GhcRn (LHsCmd GhcRn)
matches)
  = MatchGroup GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesMatch MatchGroup GhcRn (LHsCmd GhcRn)
matches FreeVars -> Name -> FreeVars
`addOneFV` Name
choiceAName
methodNamesCmd (HsCmdLamCase XCmdLamCase GhcRn
_ MatchGroup GhcRn (LHsCmd GhcRn)
matches)
  = MatchGroup GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesMatch MatchGroup GhcRn (LHsCmd GhcRn)
matches FreeVars -> Name -> FreeVars
`addOneFV` Name
choiceAName

--methodNamesCmd _ = emptyFVs
   -- Other forms can't occur in commands, but it's not convenient
   -- to error here so we just do what's convenient.
   -- The type checker will complain later

---------------------------------------------------
methodNamesMatch :: MatchGroup GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesMatch :: MatchGroup GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesMatch (MG { mg_alts :: forall p body. MatchGroup p body -> Located [LMatch p body]
mg_alts = L SrcSpan
_ [LMatch GhcRn (LHsCmd GhcRn)]
ms })
  = [FreeVars] -> FreeVars
plusFVs ((LMatch GhcRn (LHsCmd GhcRn) -> FreeVars)
-> [LMatch GhcRn (LHsCmd GhcRn)] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map LMatch GhcRn (LHsCmd GhcRn) -> FreeVars
forall {l}. GenLocated l (Match GhcRn (LHsCmd GhcRn)) -> FreeVars
do_one [LMatch GhcRn (LHsCmd GhcRn)]
ms)
 where
    do_one :: GenLocated l (Match GhcRn (LHsCmd GhcRn)) -> FreeVars
do_one (L l
_ (Match { m_grhss :: forall p body. Match p body -> GRHSs p body
m_grhss = GRHSs GhcRn (LHsCmd GhcRn)
grhss })) = GRHSs GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesGRHSs GRHSs GhcRn (LHsCmd GhcRn)
grhss

-------------------------------------------------
-- gaw 2004
methodNamesGRHSs :: GRHSs GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesGRHSs :: GRHSs GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesGRHSs (GRHSs XCGRHSs GhcRn (LHsCmd GhcRn)
_ [LGRHS GhcRn (LHsCmd GhcRn)]
grhss LHsLocalBinds GhcRn
_) = [FreeVars] -> FreeVars
plusFVs ((LGRHS GhcRn (LHsCmd GhcRn) -> FreeVars)
-> [LGRHS GhcRn (LHsCmd GhcRn)] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map LGRHS GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesGRHS [LGRHS GhcRn (LHsCmd GhcRn)]
grhss)

-------------------------------------------------

methodNamesGRHS :: Located (GRHS GhcRn (LHsCmd GhcRn)) -> CmdNeeds
methodNamesGRHS :: LGRHS GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesGRHS (L SrcSpan
_ (GRHS XCGRHS GhcRn (LHsCmd GhcRn)
_ [ExprLStmt GhcRn]
_ LHsCmd GhcRn
rhs)) = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
rhs

---------------------------------------------------
methodNamesStmts :: [Located (StmtLR GhcRn GhcRn (LHsCmd GhcRn))] -> FreeVars
methodNamesStmts :: [LStmt GhcRn (LHsCmd GhcRn)] -> FreeVars
methodNamesStmts [LStmt GhcRn (LHsCmd GhcRn)]
stmts = [FreeVars] -> FreeVars
plusFVs ((LStmt GhcRn (LHsCmd GhcRn) -> FreeVars)
-> [LStmt GhcRn (LHsCmd GhcRn)] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map LStmt GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesLStmt [LStmt GhcRn (LHsCmd GhcRn)]
stmts)

---------------------------------------------------
methodNamesLStmt :: Located (StmtLR GhcRn GhcRn (LHsCmd GhcRn)) -> FreeVars
methodNamesLStmt :: LStmt GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesLStmt = StmtLR GhcRn GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesStmt (StmtLR GhcRn GhcRn (LHsCmd GhcRn) -> FreeVars)
-> (LStmt GhcRn (LHsCmd GhcRn)
    -> StmtLR GhcRn GhcRn (LHsCmd GhcRn))
-> LStmt GhcRn (LHsCmd GhcRn)
-> FreeVars
forall b c a. (b -> c) -> (a -> b) -> a -> c
. LStmt GhcRn (LHsCmd GhcRn) -> StmtLR GhcRn GhcRn (LHsCmd GhcRn)
forall l e. GenLocated l e -> e
unLoc

methodNamesStmt :: StmtLR GhcRn GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesStmt :: StmtLR GhcRn GhcRn (LHsCmd GhcRn) -> FreeVars
methodNamesStmt (LastStmt XLastStmt GhcRn GhcRn (LHsCmd GhcRn)
_ LHsCmd GhcRn
cmd Maybe Bool
_ SyntaxExpr GhcRn
_)           = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
cmd
methodNamesStmt (BodyStmt XBodyStmt GhcRn GhcRn (LHsCmd GhcRn)
_ LHsCmd GhcRn
cmd SyntaxExpr GhcRn
_ SyntaxExpr GhcRn
_)           = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
cmd
methodNamesStmt (BindStmt XBindStmt GhcRn GhcRn (LHsCmd GhcRn)
_ LPat GhcRn
_ LHsCmd GhcRn
cmd)             = LHsCmd GhcRn -> FreeVars
methodNamesLCmd LHsCmd GhcRn
cmd
methodNamesStmt (RecStmt { recS_stmts :: forall idL idR body. StmtLR idL idR body -> [LStmtLR idL idR body]
recS_stmts = [LStmt GhcRn (LHsCmd GhcRn)]
stmts }) =
  [LStmt GhcRn (LHsCmd GhcRn)] -> FreeVars
methodNamesStmts [LStmt GhcRn (LHsCmd GhcRn)]
stmts FreeVars -> Name -> FreeVars
`addOneFV` Name
loopAName
methodNamesStmt (LetStmt {})                   = FreeVars
emptyFVs
methodNamesStmt (ParStmt {})                   = FreeVars
emptyFVs
methodNamesStmt (TransStmt {})                 = FreeVars
emptyFVs
methodNamesStmt ApplicativeStmt{}              = FreeVars
emptyFVs
   -- ParStmt and TransStmt can't occur in commands, but it's not
   -- convenient to error here so we just do what's convenient

{-
************************************************************************
*                                                                      *
        Arithmetic sequences
*                                                                      *
************************************************************************
-}

rnArithSeq :: ArithSeqInfo GhcPs -> RnM (ArithSeqInfo GhcRn, FreeVars)
rnArithSeq :: ArithSeqInfo GhcPs -> RnM (ArithSeqInfo GhcRn, FreeVars)
rnArithSeq (From LHsExpr GhcPs
expr)
 = do { (LHsExpr GhcRn
expr', FreeVars
fvExpr) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
      ; (ArithSeqInfo GhcRn, FreeVars)
-> RnM (ArithSeqInfo GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn -> ArithSeqInfo GhcRn
forall id. LHsExpr id -> ArithSeqInfo id
From LHsExpr GhcRn
expr', FreeVars
fvExpr) }

rnArithSeq (FromThen LHsExpr GhcPs
expr1 LHsExpr GhcPs
expr2)
 = do { (LHsExpr GhcRn
expr1', FreeVars
fvExpr1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr1
      ; (LHsExpr GhcRn
expr2', FreeVars
fvExpr2) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr2
      ; (ArithSeqInfo GhcRn, FreeVars)
-> RnM (ArithSeqInfo GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn -> LHsExpr GhcRn -> ArithSeqInfo GhcRn
forall id. LHsExpr id -> LHsExpr id -> ArithSeqInfo id
FromThen LHsExpr GhcRn
expr1' LHsExpr GhcRn
expr2', FreeVars
fvExpr1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvExpr2) }

rnArithSeq (FromTo LHsExpr GhcPs
expr1 LHsExpr GhcPs
expr2)
 = do { (LHsExpr GhcRn
expr1', FreeVars
fvExpr1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr1
      ; (LHsExpr GhcRn
expr2', FreeVars
fvExpr2) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr2
      ; (ArithSeqInfo GhcRn, FreeVars)
-> RnM (ArithSeqInfo GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn -> LHsExpr GhcRn -> ArithSeqInfo GhcRn
forall id. LHsExpr id -> LHsExpr id -> ArithSeqInfo id
FromTo LHsExpr GhcRn
expr1' LHsExpr GhcRn
expr2', FreeVars
fvExpr1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvExpr2) }

rnArithSeq (FromThenTo LHsExpr GhcPs
expr1 LHsExpr GhcPs
expr2 LHsExpr GhcPs
expr3)
 = do { (LHsExpr GhcRn
expr1', FreeVars
fvExpr1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr1
      ; (LHsExpr GhcRn
expr2', FreeVars
fvExpr2) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr2
      ; (LHsExpr GhcRn
expr3', FreeVars
fvExpr3) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr3
      ; (ArithSeqInfo GhcRn, FreeVars)
-> RnM (ArithSeqInfo GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn
-> LHsExpr GhcRn -> LHsExpr GhcRn -> ArithSeqInfo GhcRn
forall id.
LHsExpr id -> LHsExpr id -> LHsExpr id -> ArithSeqInfo id
FromThenTo LHsExpr GhcRn
expr1' LHsExpr GhcRn
expr2' LHsExpr GhcRn
expr3',
                [FreeVars] -> FreeVars
plusFVs [FreeVars
fvExpr1, FreeVars
fvExpr2, FreeVars
fvExpr3]) }

{-
************************************************************************
*                                                                      *
\subsubsection{@Stmt@s: in @do@ expressions}
*                                                                      *
************************************************************************
-}

{-
Note [Deterministic ApplicativeDo and RecursiveDo desugaring]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Both ApplicativeDo and RecursiveDo need to create tuples not
present in the source text.

For ApplicativeDo we create:

  (a,b,c) <- (\c b a -> (a,b,c)) <$>

For RecursiveDo we create:

  mfix (\ ~(a,b,c) -> do ...; return (a',b',c'))

The order of the components in those tuples needs to be stable
across recompilations, otherwise they can get optimized differently
and we end up with incompatible binaries.
To get a stable order we use nameSetElemsStable.
See Note [Deterministic UniqFM] to learn more about nondeterminism.
-}

-- | Rename some Stmts
rnStmts :: Outputable (body GhcPs)
        => HsStmtContext GhcRn
        -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
           -- ^ How to rename the body of each statement (e.g. rnLExpr)
        -> [LStmt GhcPs (Located (body GhcPs))]
           -- ^ Statements
        -> ([Name] -> RnM (thing, FreeVars))
           -- ^ if these statements scope over something, this renames it
           -- and returns the result.
        -> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmts :: forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmts HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody = HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> (HsStmtContext GhcRn
    -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
    -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> (HsStmtContext GhcRn
    -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
    -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmtsWithPostProcessing HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
forall (body :: * -> *).
HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
noPostProcessStmts

-- | like 'rnStmts' but applies a post-processing step to the renamed Stmts
rnStmtsWithPostProcessing
        :: Outputable (body GhcPs)
        => HsStmtContext GhcRn
        -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
           -- ^ How to rename the body of each statement (e.g. rnLExpr)
        -> (HsStmtContext GhcRn
              -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
              -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars))
           -- ^ postprocess the statements
        -> [LStmt GhcPs (Located (body GhcPs))]
           -- ^ Statements
        -> ([Name] -> RnM (thing, FreeVars))
           -- ^ if these statements scope over something, this renames it
           -- and returns the result.
        -> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmtsWithPostProcessing :: forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> (HsStmtContext GhcRn
    -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
    -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmtsWithPostProcessing HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
ppStmts [LStmt GhcPs (Located (body GhcPs))]
stmts [Name] -> RnM (thing, FreeVars)
thing_inside
 = do { (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts', thing
thing), FreeVars
fvs) <-
          HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmtsWithFreeVars HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [LStmt GhcPs (Located (body GhcPs))]
stmts [Name] -> RnM (thing, FreeVars)
thing_inside
      ; ([LStmt GhcRn (Located (body GhcRn))]
pp_stmts, FreeVars
fvs') <- HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
ppStmts HsStmtContext GhcRn
ctxt [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts'
      ; (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([LStmt GhcRn (Located (body GhcRn))]
pp_stmts, thing
thing), FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs')
      }

-- | maybe rearrange statements according to the ApplicativeDo transformation
postProcessStmtsForApplicativeDo
  :: HsStmtContext GhcRn
  -> [(ExprLStmt GhcRn, FreeVars)]
  -> RnM ([ExprLStmt GhcRn], FreeVars)
postProcessStmtsForApplicativeDo :: HsStmtContext GhcRn
-> [(ExprLStmt GhcRn, FreeVars)]
-> RnM ([ExprLStmt GhcRn], FreeVars)
postProcessStmtsForApplicativeDo HsStmtContext GhcRn
ctxt [(ExprLStmt GhcRn, FreeVars)]
stmts
  = do {
       -- rearrange the statements using ApplicativeStmt if
       -- -XApplicativeDo is on.  Also strip out the FreeVars attached
       -- to each Stmt body.
         Bool
ado_is_on <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.ApplicativeDo
       ; let is_do_expr :: Bool
is_do_expr | DoExpr{} <- HsStmtContext GhcRn
ctxt = Bool
True
                        | Bool
otherwise = Bool
False
       -- don't apply the transformation inside TH brackets, because
       -- GHC.HsToCore.Quote does not handle ApplicativeDo.
       ; Bool
in_th_bracket <- ThStage -> Bool
isBrackStage (ThStage -> Bool) -> TcM ThStage -> TcRnIf TcGblEnv TcLclEnv Bool
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> TcM ThStage
getStage
       ; if Bool
ado_is_on Bool -> Bool -> Bool
&& Bool
is_do_expr Bool -> Bool -> Bool
&& Bool -> Bool
not Bool
in_th_bracket
            then do { String -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
traceRn String
"ppsfa" ([(ExprLStmt GhcRn, FreeVars)] -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr [(ExprLStmt GhcRn, FreeVars)]
stmts)
                    ; HsStmtContext GhcRn
-> [(ExprLStmt GhcRn, FreeVars)]
-> RnM ([ExprLStmt GhcRn], FreeVars)
rearrangeForApplicativeDo HsStmtContext GhcRn
ctxt [(ExprLStmt GhcRn, FreeVars)]
stmts }
            else HsStmtContext GhcRn
-> [(ExprLStmt GhcRn, FreeVars)]
-> RnM ([ExprLStmt GhcRn], FreeVars)
forall (body :: * -> *).
HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
noPostProcessStmts HsStmtContext GhcRn
ctxt [(ExprLStmt GhcRn, FreeVars)]
stmts }

-- | strip the FreeVars annotations from statements
noPostProcessStmts
  :: HsStmtContext GhcRn
  -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
  -> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
noPostProcessStmts :: forall (body :: * -> *).
HsStmtContext GhcRn
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> RnM ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
noPostProcessStmts HsStmtContext GhcRn
_ [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts = ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (((LStmt GhcRn (Located (body GhcRn)), FreeVars)
 -> LStmt GhcRn (Located (body GhcRn)))
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [LStmt GhcRn (Located (body GhcRn))]
forall a b. (a -> b) -> [a] -> [b]
map (LStmt GhcRn (Located (body GhcRn)), FreeVars)
-> LStmt GhcRn (Located (body GhcRn))
forall a b. (a, b) -> a
fst [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts, FreeVars
emptyNameSet)


rnStmtsWithFreeVars :: Outputable (body GhcPs)
        => HsStmtContext GhcRn
        -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
        -> [LStmt GhcPs (Located (body GhcPs))]
        -> ([Name] -> RnM (thing, FreeVars))
        -> RnM ( ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)
               , FreeVars)
-- Each Stmt body is annotated with its FreeVars, so that
-- we can rearrange statements for ApplicativeDo.
--
-- Variables bound by the Stmts, and mentioned in thing_inside,
-- do not appear in the result FreeVars

rnStmtsWithFreeVars :: forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmtsWithFreeVars HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [] [Name] -> RnM (thing, FreeVars)
thing_inside
  = do { HsStmtContext GhcRn -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkEmptyStmts HsStmtContext GhcRn
ctxt
       ; (thing
thing, FreeVars
fvs) <- [Name] -> RnM (thing, FreeVars)
thing_inside []
       ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([], thing
thing), FreeVars
fvs) }

rnStmtsWithFreeVars mDoExpr :: HsStmtContext GhcRn
mDoExpr@MDoExpr{} Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [LStmt GhcPs (Located (body GhcPs))]
stmts [Name] -> RnM (thing, FreeVars)
thing_inside    -- Deal with mdo
  = -- Behave like do { rec { ...all but last... }; last }
    do { (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts1, ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts2, thing
thing)), FreeVars
fvs)
           <- HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmt HsStmtContext GhcRn
mDoExpr Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (StmtLR GhcPs GhcPs (Located (body GhcPs))
-> LStmt GhcPs (Located (body GhcPs))
forall e. e -> Located e
noLoc (StmtLR GhcPs GhcPs (Located (body GhcPs))
 -> LStmt GhcPs (Located (body GhcPs)))
-> StmtLR GhcPs GhcPs (Located (body GhcPs))
-> LStmt GhcPs (Located (body GhcPs))
forall a b. (a -> b) -> a -> b
$ [LStmt GhcPs (Located (body GhcPs))]
-> StmtLR GhcPs GhcPs (Located (body GhcPs))
forall (idL :: Pass) bodyR.
[LStmtLR (GhcPass idL) GhcPs bodyR]
-> StmtLR (GhcPass idL) GhcPs bodyR
mkRecStmt [LStmt GhcPs (Located (body GhcPs))]
all_but_last) (([Name]
  -> RnM
       (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
        FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
        ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
       FreeVars))
-> ([Name]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Name]
_ ->
              do { LStmt GhcPs (Located (body GhcPs))
last_stmt' <- HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
checkLastStmt HsStmtContext GhcRn
mDoExpr LStmt GhcPs (Located (body GhcPs))
last_stmt
                 ; HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmt HsStmtContext GhcRn
mDoExpr Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody LStmt GhcPs (Located (body GhcPs))
last_stmt' [Name] -> RnM (thing, FreeVars)
thing_inside }
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts1 [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
forall a. [a] -> [a] -> [a]
++ [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts2), thing
thing), FreeVars
fvs) }
  where
    Just ([LStmt GhcPs (Located (body GhcPs))]
all_but_last, LStmt GhcPs (Located (body GhcPs))
last_stmt) = [LStmt GhcPs (Located (body GhcPs))]
-> Maybe
     ([LStmt GhcPs (Located (body GhcPs))],
      LStmt GhcPs (Located (body GhcPs)))
forall a. [a] -> Maybe ([a], a)
snocView [LStmt GhcPs (Located (body GhcPs))]
stmts

rnStmtsWithFreeVars HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (lstmt :: LStmt GhcPs (Located (body GhcPs))
lstmt@(L SrcSpan
loc StmtLR GhcPs GhcPs (Located (body GhcPs))
_) : [LStmt GhcPs (Located (body GhcPs))]
lstmts) [Name] -> RnM (thing, FreeVars)
thing_inside
  | [LStmt GhcPs (Located (body GhcPs))] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [LStmt GhcPs (Located (body GhcPs))]
lstmts
  = SrcSpan
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a. SrcSpan -> TcRn a -> TcRn a
setSrcSpan SrcSpan
loc (RnM
   (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
    FreeVars)
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
       FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a b. (a -> b) -> a -> b
$
    do { LStmt GhcPs (Located (body GhcPs))
lstmt' <- HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
checkLastStmt HsStmtContext GhcRn
ctxt LStmt GhcPs (Located (body GhcPs))
lstmt
       ; HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody LStmt GhcPs (Located (body GhcPs))
lstmt' [Name] -> RnM (thing, FreeVars)
thing_inside }

  | Bool
otherwise
  = do { (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts1, ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts2, thing
thing)), FreeVars
fvs)
            <- SrcSpan
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall a. SrcSpan -> TcRn a -> TcRn a
setSrcSpan SrcSpan
loc                         (RnM
   (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
     ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
    FreeVars)
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
        ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
       FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall a b. (a -> b) -> a -> b
$
               do { HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (body :: * -> *).
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> IOEnv (Env TcGblEnv TcLclEnv) ()
checkStmt HsStmtContext GhcRn
ctxt LStmt GhcPs (Located (body GhcPs))
lstmt
                  ; HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody LStmt GhcPs (Located (body GhcPs))
lstmt    (([Name]
  -> RnM
       (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
        FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
        ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
       FreeVars))
-> ([Name]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
       ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Name]
bndrs1 ->
                    HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmtsWithFreeVars HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [LStmt GhcPs (Located (body GhcPs))]
lstmts  (([Name] -> RnM (thing, FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
       FreeVars))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Name]
bndrs2 ->
                    [Name] -> RnM (thing, FreeVars)
thing_inside ([Name]
bndrs1 [Name] -> [Name] -> [Name]
forall a. [a] -> [a] -> [a]
++ [Name]
bndrs2) }
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((([(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts1 [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
forall a. [a] -> [a] -> [a]
++ [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts2), thing
thing), FreeVars
fvs) }

----------------------

{-
Note [Failing pattern matches in Stmts]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Many things desugar to HsStmts including monadic things like `do` and `mdo`
statements, pattern guards, and list comprehensions (see 'HsStmtContext' for an
exhaustive list). How we deal with pattern match failure is context-dependent.

 * In the case of list comprehensions and pattern guards we don't need any
   'fail' function; the desugarer ignores the fail function of 'BindStmt'
   entirely. So, for list comprehensions, the fail function is set to 'Nothing'
   for clarity.

 * In the case of monadic contexts (e.g. monad comprehensions, do, and mdo
   expressions) we want pattern match failure to be desugared to the appropriate
   'fail' function (either that of Monad or MonadFail, depending on whether
   -XMonadFailDesugaring is enabled.)

At one point we failed to make this distinction, leading to #11216.
-}

rnStmt :: Outputable (body GhcPs)
       => HsStmtContext GhcRn
       -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
          -- ^ How to rename the body of the statement
       -> LStmt GhcPs (Located (body GhcPs))
          -- ^ The statement
       -> ([Name] -> RnM (thing, FreeVars))
          -- ^ Rename the stuff that this statement scopes over
       -> RnM ( ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing)
              , FreeVars)
-- Variables bound by the Stmt, and mentioned in thing_inside,
-- do not appear in the result FreeVars

rnStmt :: forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> LStmt GhcPs (Located (body GhcPs))
-> ([Name] -> RnM (thing, FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (L SrcSpan
loc (LastStmt XLastStmt GhcPs GhcPs (Located (body GhcPs))
_ Located (body GhcPs)
body Maybe Bool
noret SyntaxExpr GhcPs
_)) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { (Located (body GhcRn)
body', FreeVars
fv_expr) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
        ; (SyntaxExprRn
ret_op, FreeVars
fvs1) <- if HsStmtContext GhcRn -> Bool
forall id. HsStmtContext id -> Bool
isMonadCompContext HsStmtContext GhcRn
ctxt
                            then HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
returnMName
                            else (SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExprRn
forall (p :: Pass). IsPass p => SyntaxExpr (GhcPass p)
noSyntaxExpr, FreeVars
emptyFVs)
                            -- The 'return' in a LastStmt is used only
                            -- for MonadComp; and we don't want to report
                            -- "non in scope: return" in other cases
                            -- #15607

        ; (thing
thing,  FreeVars
fvs3) <- [Name] -> RnM (thing, FreeVars)
thing_inside []
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([(SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLastStmt GhcRn GhcRn (Located (body GhcRn))
-> Located (body GhcRn)
-> Maybe Bool
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XLastStmt idL idR body
-> body -> Maybe Bool -> SyntaxExpr idR -> StmtLR idL idR body
LastStmt NoExtField
XLastStmt GhcRn GhcRn (Located (body GhcRn))
noExtField Located (body GhcRn)
body' Maybe Bool
noret SyntaxExpr GhcRn
SyntaxExprRn
ret_op), FreeVars
fv_expr)]
                  , thing
thing), FreeVars
fv_expr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3) }

rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (L SrcSpan
loc (BodyStmt XBodyStmt GhcPs GhcPs (Located (body GhcPs))
_ Located (body GhcPs)
body SyntaxExpr GhcPs
_ SyntaxExpr GhcPs
_)) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { (Located (body GhcRn)
body', FreeVars
fv_expr) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
        ; (SyntaxExprRn
then_op, FreeVars
fvs1)  <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
thenMName

        ; (SyntaxExprRn
guard_op, FreeVars
fvs2) <- if HsStmtContext GhcRn -> Bool
forall id. HsStmtContext id -> Bool
isComprehensionContext HsStmtContext GhcRn
ctxt
                              then HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
guardMName
                              else (SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExprRn
forall (p :: Pass). IsPass p => SyntaxExpr (GhcPass p)
noSyntaxExpr, FreeVars
emptyFVs)
                              -- Only list/monad comprehensions use 'guard'
                              -- Also for sub-stmts of same eg [ e | x<-xs, gd | blah ]
                              -- Here "gd" is a guard

        ; (thing
thing, FreeVars
fvs3)    <- [Name] -> RnM (thing, FreeVars)
thing_inside []
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( ([(SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBodyStmt GhcRn GhcRn (Located (body GhcRn))
-> Located (body GhcRn)
-> SyntaxExpr GhcRn
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XBodyStmt idL idR body
-> body -> SyntaxExpr idR -> SyntaxExpr idR -> StmtLR idL idR body
BodyStmt NoExtField
XBodyStmt GhcRn GhcRn (Located (body GhcRn))
noExtField Located (body GhcRn)
body' SyntaxExpr GhcRn
SyntaxExprRn
then_op SyntaxExpr GhcRn
SyntaxExprRn
guard_op), FreeVars
fv_expr)]
                  , thing
thing), FreeVars
fv_expr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3) }

rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (L SrcSpan
loc (BindStmt XBindStmt GhcPs GhcPs (Located (body GhcPs))
_ LPat GhcPs
pat Located (body GhcPs)
body)) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { (Located (body GhcRn)
body', FreeVars
fv_expr) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
                -- The binders do not scope over the expression
        ; (SyntaxExprRn
bind_op, FreeVars
fvs1) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
bindMName

        ; (Maybe SyntaxExprRn
fail_op, FreeVars
fvs2) <- LPat GhcPs
-> HsStmtContext GhcRn -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
monadFailOp LPat GhcPs
pat HsStmtContext GhcRn
ctxt

        ; HsMatchContext GhcRn
-> LPat GhcPs
-> (LPat GhcRn
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a.
HsMatchContext GhcRn
-> LPat GhcPs
-> (LPat GhcRn -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnPat (HsStmtContext GhcRn -> HsMatchContext GhcRn
forall p. HsStmtContext p -> HsMatchContext p
StmtCtxt HsStmtContext GhcRn
ctxt) LPat GhcPs
pat ((LPat GhcRn
  -> RnM
       (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
        FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
       FreeVars))
-> (LPat GhcRn
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ LPat GhcRn
pat' -> do
        { (thing
thing, FreeVars
fvs3) <- [Name] -> RnM (thing, FreeVars)
thing_inside (LPat GhcRn -> [IdP GhcRn]
forall p. CollectPass p => LPat p -> [IdP p]
collectPatBinders LPat GhcRn
pat')
        ; let xbsrn :: XBindStmtRn
xbsrn = XBindStmtRn :: SyntaxExpr GhcRn -> Maybe (SyntaxExpr GhcRn) -> XBindStmtRn
XBindStmtRn { xbsrn_bindOp :: SyntaxExpr GhcRn
xbsrn_bindOp = SyntaxExpr GhcRn
SyntaxExprRn
bind_op, xbsrn_failOp :: Maybe (SyntaxExpr GhcRn)
xbsrn_failOp = Maybe (SyntaxExpr GhcRn)
Maybe SyntaxExprRn
fail_op }
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (( [( SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBindStmt GhcRn GhcRn (Located (body GhcRn))
-> LPat GhcRn
-> Located (body GhcRn)
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XBindStmt idL idR body -> LPat idL -> body -> StmtLR idL idR body
BindStmt XBindStmt GhcRn GhcRn (Located (body GhcRn))
XBindStmtRn
xbsrn LPat GhcRn
pat' Located (body GhcRn)
body'), FreeVars
fv_expr )]
                  , thing
thing),
                  FreeVars
fv_expr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3) }}
       -- fv_expr shouldn't really be filtered by the rnPatsAndThen
        -- but it does not matter because the names are unique

rnStmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ (L SrcSpan
loc (LetStmt XLetStmt GhcPs GhcPs (Located (body GhcPs))
_ (L SrcSpan
l HsLocalBinds GhcPs
binds))) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn
    -> FreeVars
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall result.
HsLocalBinds GhcPs
-> (HsLocalBinds GhcRn -> FreeVars -> RnM (result, FreeVars))
-> RnM (result, FreeVars)
rnLocalBindsAndThen HsLocalBinds GhcPs
binds ((HsLocalBinds GhcRn
  -> FreeVars
  -> RnM
       (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
        FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
       FreeVars))
-> (HsLocalBinds GhcRn
    -> FreeVars
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \HsLocalBinds GhcRn
binds' FreeVars
bind_fvs -> do
        { (thing
thing, FreeVars
fvs) <- [Name] -> RnM (thing, FreeVars)
thing_inside (HsLocalBinds GhcRn -> [IdP GhcRn]
forall (idL :: Pass) (idR :: Pass).
CollectPass (GhcPass idL) =>
HsLocalBindsLR (GhcPass idL) (GhcPass idR) -> [IdP (GhcPass idL)]
collectLocalBinders HsLocalBinds GhcRn
binds')
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( ([(SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLetStmt GhcRn GhcRn (Located (body GhcRn))
-> LHsLocalBinds GhcRn -> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XLetStmt idL idR body
-> LHsLocalBindsLR idL idR -> StmtLR idL idR body
LetStmt NoExtField
XLetStmt GhcRn GhcRn (Located (body GhcRn))
noExtField (SrcSpan -> HsLocalBinds GhcRn -> LHsLocalBinds GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
l HsLocalBinds GhcRn
binds')), FreeVars
bind_fvs)], thing
thing)
                 , FreeVars
fvs) }  }

rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody (L SrcSpan
loc (RecStmt { recS_stmts :: forall idL idR body. StmtLR idL idR body -> [LStmtLR idL idR body]
recS_stmts = [GenLocated SrcSpan (StmtLR GhcPs GhcPs (Located (body GhcPs)))]
rec_stmts })) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { (SyntaxExprRn
return_op, FreeVars
fvs1)  <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
returnMName
        ; (SyntaxExprRn
mfix_op,   FreeVars
fvs2)  <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
mfixName
        ; (SyntaxExprRn
bind_op,   FreeVars
fvs3)  <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
bindMName
        ; let empty_rec_stmt :: StmtLR GhcRn GhcRn (Located (body GhcRn))
empty_rec_stmt = StmtLR GhcRn GhcRn (Located (body GhcRn))
forall bodyR. StmtLR GhcRn GhcRn bodyR
emptyRecStmtName { recS_ret_fn :: SyntaxExpr GhcRn
recS_ret_fn  = SyntaxExpr GhcRn
SyntaxExprRn
return_op
                                                , recS_mfix_fn :: SyntaxExpr GhcRn
recS_mfix_fn = SyntaxExpr GhcRn
SyntaxExprRn
mfix_op
                                                , recS_bind_fn :: SyntaxExpr GhcRn
recS_bind_fn = SyntaxExpr GhcRn
SyntaxExprRn
bind_op }

        -- Step1: Bring all the binders of the mdo into scope
        -- (Remember that this also removes the binders from the
        -- finally-returned free-vars.)
        -- And rename each individual stmt, making a
        -- singleton segment.  At this stage the FwdRefs field
        -- isn't finished: it's empty for all except a BindStmt
        -- for which it's the fwd refs within the bind itself
        -- (This set may not be empty, because we're in a recursive
        -- context.)
        ; HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [GenLocated SrcSpan (StmtLR GhcPs GhcPs (Located (body GhcPs)))]
-> ([Segment (LStmt GhcRn (Located (body GhcRn)))]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (body :: * -> *) a.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Segment (LStmt GhcRn (Located (body GhcRn)))]
    -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnRecStmtsAndThen HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [GenLocated SrcSpan (StmtLR GhcPs GhcPs (Located (body GhcPs)))]
rec_stmts   (([Segment (LStmt GhcRn (Located (body GhcRn)))]
  -> RnM
       (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
        FreeVars))
 -> RnM
      (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
       FreeVars))
-> ([Segment (LStmt GhcRn (Located (body GhcRn)))]
    -> RnM
         (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
          FreeVars))
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Segment (LStmt GhcRn (Located (body GhcRn)))]
segs -> do
        { let bndrs :: [Name]
bndrs = FreeVars -> [Name]
nameSetElemsStable (FreeVars -> [Name]) -> FreeVars -> [Name]
forall a b. (a -> b) -> a -> b
$
                        (Segment (LStmt GhcRn (Located (body GhcRn)))
 -> FreeVars -> FreeVars)
-> FreeVars
-> [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> FreeVars
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr (FreeVars -> FreeVars -> FreeVars
unionNameSet (FreeVars -> FreeVars -> FreeVars)
-> (Segment (LStmt GhcRn (Located (body GhcRn))) -> FreeVars)
-> Segment (LStmt GhcRn (Located (body GhcRn)))
-> FreeVars
-> FreeVars
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (\(FreeVars
ds,FreeVars
_,FreeVars
_,LStmt GhcRn (Located (body GhcRn))
_) -> FreeVars
ds))
                              FreeVars
emptyNameSet
                              [Segment (LStmt GhcRn (Located (body GhcRn)))]
segs
          -- See Note [Deterministic ApplicativeDo and RecursiveDo desugaring]
        ; (thing
thing, FreeVars
fvs_later) <- [Name] -> RnM (thing, FreeVars)
thing_inside [Name]
bndrs
        ; let ([LStmt GhcRn (Located (body GhcRn))]
rec_stmts', FreeVars
fvs) = SrcSpan
-> HsStmtContext GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> FreeVars
-> ([LStmt GhcRn (Located (body GhcRn))], FreeVars)
forall body.
SrcSpan
-> HsStmtContext GhcRn
-> Stmt GhcRn body
-> [Segment (LStmt GhcRn body)]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
segmentRecStmts SrcSpan
loc HsStmtContext GhcRn
ctxt StmtLR GhcRn GhcRn (Located (body GhcRn))
empty_rec_stmt [Segment (LStmt GhcRn (Located (body GhcRn)))]
segs FreeVars
fvs_later
        -- We aren't going to try to group RecStmts with
        -- ApplicativeDo, so attaching empty FVs is fine.
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( (([LStmt GhcRn (Located (body GhcRn))]
-> [FreeVars] -> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
forall a b. [a] -> [b] -> [(a, b)]
zip [LStmt GhcRn (Located (body GhcRn))]
rec_stmts' (FreeVars -> [FreeVars]
forall a. a -> [a]
repeat FreeVars
emptyNameSet)), thing
thing)
                 , FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3) } }

rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ (L SrcSpan
loc (ParStmt XParStmt GhcPs GhcPs (Located (body GhcPs))
_ [ParStmtBlock GhcPs GhcPs]
segs HsExpr GhcPs
_ SyntaxExpr GhcPs
_)) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do  { (HsExpr GhcRn
mzip_op, FreeVars
fvs1)   <- HsStmtContext GhcRn -> Name -> TcM (HsExpr GhcRn, FreeVars)
lookupStmtNamePoly HsStmtContext GhcRn
ctxt Name
mzipName
        ; (SyntaxExprRn
bind_op, FreeVars
fvs2)   <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
bindMName
        ; (SyntaxExprRn
return_op, FreeVars
fvs3) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
returnMName
        ; (([ParStmtBlock GhcRn GhcRn]
segs', thing
thing), FreeVars
fvs4) <- HsStmtContext GhcRn
-> SyntaxExpr GhcRn
-> [ParStmtBlock GhcPs GhcPs]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall thing.
HsStmtContext GhcRn
-> SyntaxExpr GhcRn
-> [ParStmtBlock GhcPs GhcPs]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
rnParallelStmts (HsStmtContext GhcRn -> HsStmtContext GhcRn
forall p. HsStmtContext p -> HsStmtContext p
ParStmtCtxt HsStmtContext GhcRn
ctxt) SyntaxExpr GhcRn
SyntaxExprRn
return_op [ParStmtBlock GhcPs GhcPs]
segs [Name] -> RnM (thing, FreeVars)
thing_inside
        ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([(SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XParStmt GhcRn GhcRn (Located (body GhcRn))
-> [ParStmtBlock GhcRn GhcRn]
-> HsExpr GhcRn
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XParStmt idL idR body
-> [ParStmtBlock idL idR]
-> HsExpr idR
-> SyntaxExpr idR
-> StmtLR idL idR body
ParStmt NoExtField
XParStmt GhcRn GhcRn (Located (body GhcRn))
noExtField [ParStmtBlock GhcRn GhcRn]
segs' HsExpr GhcRn
mzip_op SyntaxExpr GhcRn
SyntaxExprRn
bind_op), FreeVars
fvs4)], thing
thing)
                 , FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs4) }

rnStmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ (L SrcSpan
loc (TransStmt { trS_stmts :: forall idL idR body. StmtLR idL idR body -> [ExprLStmt idL]
trS_stmts = [ExprLStmt GhcPs]
stmts, trS_by :: forall idL idR body. StmtLR idL idR body -> Maybe (LHsExpr idR)
trS_by = Maybe (LHsExpr GhcPs)
by, trS_form :: forall idL idR body. StmtLR idL idR body -> TransForm
trS_form = TransForm
form
                              , trS_using :: forall idL idR body. StmtLR idL idR body -> LHsExpr idR
trS_using = LHsExpr GhcPs
using })) [Name] -> RnM (thing, FreeVars)
thing_inside
  = do { -- Rename the 'using' expression in the context before the transform is begun
         (LHsExpr GhcRn
using', FreeVars
fvs1) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
using

         -- Rename the stmts and the 'by' expression
         -- Keep track of the variables mentioned in the 'by' expression
       ; (([ExprLStmt GhcRn]
stmts', (Maybe (LHsExpr GhcRn)
by', [Name]
used_bndrs, thing
thing)), FreeVars
fvs2)
             <- HsStmtContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> [ExprLStmt GhcPs]
-> ([Name]
    -> RnM ((Maybe (LHsExpr GhcRn), [Name], thing), FreeVars))
-> RnM
     (([ExprLStmt GhcRn], (Maybe (LHsExpr GhcRn), [Name], thing)),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmts (HsStmtContext GhcRn -> HsStmtContext GhcRn
forall p. HsStmtContext p -> HsStmtContext p
TransStmtCtxt HsStmtContext GhcRn
ctxt) LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr [ExprLStmt GhcPs]
stmts (([Name] -> RnM ((Maybe (LHsExpr GhcRn), [Name], thing), FreeVars))
 -> RnM
      (([ExprLStmt GhcRn], (Maybe (LHsExpr GhcRn), [Name], thing)),
       FreeVars))
-> ([Name]
    -> RnM ((Maybe (LHsExpr GhcRn), [Name], thing), FreeVars))
-> RnM
     (([ExprLStmt GhcRn], (Maybe (LHsExpr GhcRn), [Name], thing)),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Name]
bndrs ->
                do { (Maybe (LHsExpr GhcRn)
by',   FreeVars
fvs_by) <- (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> Maybe (LHsExpr GhcPs) -> RnM (Maybe (LHsExpr GhcRn), FreeVars)
forall a b.
(a -> RnM (b, FreeVars)) -> Maybe a -> RnM (Maybe b, FreeVars)
mapMaybeFvRn LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr Maybe (LHsExpr GhcPs)
by
                   ; (thing
thing, FreeVars
fvs_thing) <- [Name] -> RnM (thing, FreeVars)
thing_inside [Name]
bndrs
                   ; let fvs :: FreeVars
fvs = FreeVars
fvs_by FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs_thing
                         used_bndrs :: [Name]
used_bndrs = (Name -> Bool) -> [Name] -> [Name]
forall a. (a -> Bool) -> [a] -> [a]
filter (Name -> FreeVars -> Bool
`elemNameSet` FreeVars
fvs) [Name]
bndrs
                         -- The paper (Fig 5) has a bug here; we must treat any free variable
                         -- of the "thing inside", **or of the by-expression**, as used
                   ; ((Maybe (LHsExpr GhcRn), [Name], thing), FreeVars)
-> RnM ((Maybe (LHsExpr GhcRn), [Name], thing), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((Maybe (LHsExpr GhcRn)
by', [Name]
used_bndrs, thing
thing), FreeVars
fvs) }

       -- Lookup `return`, `(>>=)` and `liftM` for monad comprehensions
       ; (SyntaxExprRn
return_op, FreeVars
fvs3) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
returnMName
       ; (SyntaxExprRn
bind_op,   FreeVars
fvs4) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
bindMName
       ; (HsExpr GhcRn
fmap_op,   FreeVars
fvs5) <- case TransForm
form of
                                TransForm
ThenForm -> (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (HsExpr GhcRn
forall (p :: Pass). HsExpr (GhcPass p)
noExpr, FreeVars
emptyFVs)
                                TransForm
_        -> HsStmtContext GhcRn -> Name -> TcM (HsExpr GhcRn, FreeVars)
lookupStmtNamePoly HsStmtContext GhcRn
ctxt Name
fmapName

       ; let all_fvs :: FreeVars
all_fvs  = FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3
                             FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs4 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs5
             bndr_map :: [(Name, Name)]
bndr_map = [Name]
used_bndrs [Name] -> [Name] -> [(Name, Name)]
forall a b. [a] -> [b] -> [(a, b)]
`zip` [Name]
used_bndrs
             -- See Note [TransStmt binder map] in GHC.Hs.Expr

       ; String -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
traceRn String
"rnStmt: implicitly rebound these used binders:" ([(Name, Name)] -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr [(Name, Name)]
bndr_map)
       ; (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
 FreeVars)
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([(SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (TransStmt :: forall idL idR body.
XTransStmt idL idR body
-> TransForm
-> [ExprLStmt idL]
-> [(IdP idR, IdP idR)]
-> LHsExpr idR
-> Maybe (LHsExpr idR)
-> SyntaxExpr idR
-> SyntaxExpr idR
-> HsExpr idR
-> StmtLR idL idR body
TransStmt { trS_ext :: XTransStmt GhcRn GhcRn (Located (body GhcRn))
trS_ext = NoExtField
XTransStmt GhcRn GhcRn (Located (body GhcRn))
noExtField
                                    , trS_stmts :: [ExprLStmt GhcRn]
trS_stmts = [ExprLStmt GhcRn]
stmts', trS_bndrs :: [(IdP GhcRn, IdP GhcRn)]
trS_bndrs = [(Name, Name)]
[(IdP GhcRn, IdP GhcRn)]
bndr_map
                                    , trS_by :: Maybe (LHsExpr GhcRn)
trS_by = Maybe (LHsExpr GhcRn)
by', trS_using :: LHsExpr GhcRn
trS_using = LHsExpr GhcRn
using', trS_form :: TransForm
trS_form = TransForm
form
                                    , trS_ret :: SyntaxExpr GhcRn
trS_ret = SyntaxExpr GhcRn
SyntaxExprRn
return_op, trS_bind :: SyntaxExpr GhcRn
trS_bind = SyntaxExpr GhcRn
SyntaxExprRn
bind_op
                                    , trS_fmap :: HsExpr GhcRn
trS_fmap = HsExpr GhcRn
fmap_op }), FreeVars
fvs2)], thing
thing), FreeVars
all_fvs) }

rnStmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ (L SrcSpan
_ ApplicativeStmt{}) [Name] -> RnM (thing, FreeVars)
_ =
  String
-> RnM
     (([(LStmt GhcRn (Located (body GhcRn)), FreeVars)], thing),
      FreeVars)
forall a. String -> a
panic String
"rnStmt: ApplicativeStmt"

rnParallelStmts :: forall thing. HsStmtContext GhcRn
                -> SyntaxExpr GhcRn
                -> [ParStmtBlock GhcPs GhcPs]
                -> ([Name] -> RnM (thing, FreeVars))
                -> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-- Note [Renaming parallel Stmts]
rnParallelStmts :: forall thing.
HsStmtContext GhcRn
-> SyntaxExpr GhcRn
-> [ParStmtBlock GhcPs GhcPs]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
rnParallelStmts HsStmtContext GhcRn
ctxt SyntaxExpr GhcRn
return_op [ParStmtBlock GhcPs GhcPs]
segs [Name] -> RnM (thing, FreeVars)
thing_inside
  = do { LocalRdrEnv
orig_lcl_env <- RnM LocalRdrEnv
getLocalRdrEnv
       ; LocalRdrEnv
-> [Name]
-> [ParStmtBlock GhcPs GhcPs]
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
rn_segs LocalRdrEnv
orig_lcl_env [] [ParStmtBlock GhcPs GhcPs]
segs }
  where
    rn_segs :: LocalRdrEnv
            -> [Name] -> [ParStmtBlock GhcPs GhcPs]
            -> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
    rn_segs :: LocalRdrEnv
-> [Name]
-> [ParStmtBlock GhcPs GhcPs]
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
rn_segs LocalRdrEnv
_ [Name]
bndrs_so_far []
      = do { let ([Name]
bndrs', [NonEmpty Name]
dups) = (Name -> Name -> Ordering) -> [Name] -> ([Name], [NonEmpty Name])
forall a. (a -> a -> Ordering) -> [a] -> ([a], [NonEmpty a])
removeDups Name -> Name -> Ordering
cmpByOcc [Name]
bndrs_so_far
           ; (NonEmpty Name -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> [NonEmpty Name] -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
mapM_ NonEmpty Name -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall {a}.
Outputable a =>
NonEmpty a -> IOEnv (Env TcGblEnv TcLclEnv) ()
dupErr [NonEmpty Name]
dups
           ; (thing
thing, FreeVars
fvs) <- [Name] -> RnM (thing, FreeVars) -> RnM (thing, FreeVars)
forall a. [Name] -> RnM a -> RnM a
bindLocalNames [Name]
bndrs' ([Name] -> RnM (thing, FreeVars)
thing_inside [Name]
bndrs')
           ; (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([], thing
thing), FreeVars
fvs) }

    rn_segs LocalRdrEnv
env [Name]
bndrs_so_far (ParStmtBlock XParStmtBlock GhcPs GhcPs
x [ExprLStmt GhcPs]
stmts [IdP GhcPs]
_ SyntaxExpr GhcPs
_ : [ParStmtBlock GhcPs GhcPs]
segs)
      = do { (([ExprLStmt GhcRn]
stmts', ([Name]
used_bndrs, [ParStmtBlock GhcRn GhcRn]
segs', thing
thing)), FreeVars
fvs)
                    <- HsStmtContext GhcRn
-> (LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars))
-> [ExprLStmt GhcPs]
-> ([Name]
    -> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars))
-> RnM
     (([ExprLStmt GhcRn], ([Name], [ParStmtBlock GhcRn GhcRn], thing)),
      FreeVars)
forall (body :: * -> *) thing.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Name] -> RnM (thing, FreeVars))
-> RnM (([LStmt GhcRn (Located (body GhcRn))], thing), FreeVars)
rnStmts HsStmtContext GhcRn
ctxt LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr [ExprLStmt GhcPs]
stmts (([Name]
  -> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars))
 -> RnM
      (([ExprLStmt GhcRn], ([Name], [ParStmtBlock GhcRn GhcRn], thing)),
       FreeVars))
-> ([Name]
    -> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars))
-> RnM
     (([ExprLStmt GhcRn], ([Name], [ParStmtBlock GhcRn GhcRn], thing)),
      FreeVars)
forall a b. (a -> b) -> a -> b
$ \ [Name]
bndrs ->
                       LocalRdrEnv
-> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall a. LocalRdrEnv -> RnM a -> RnM a
setLocalRdrEnv LocalRdrEnv
env       (RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
 -> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars))
-> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall a b. (a -> b) -> a -> b
$ do
                       { (([ParStmtBlock GhcRn GhcRn]
segs', thing
thing), FreeVars
fvs) <- LocalRdrEnv
-> [Name]
-> [ParStmtBlock GhcPs GhcPs]
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
rn_segs LocalRdrEnv
env ([Name]
bndrs [Name] -> [Name] -> [Name]
forall a. [a] -> [a] -> [a]
++ [Name]
bndrs_so_far) [ParStmtBlock GhcPs GhcPs]
segs
                       ; let used_bndrs :: [Name]
used_bndrs = (Name -> Bool) -> [Name] -> [Name]
forall a. (a -> Bool) -> [a] -> [a]
filter (Name -> FreeVars -> Bool
`elemNameSet` FreeVars
fvs) [Name]
bndrs
                       ; (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-> RnM (([Name], [ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (([Name]
used_bndrs, [ParStmtBlock GhcRn GhcRn]
segs', thing
thing), FreeVars
fvs) }

           ; let seg' :: ParStmtBlock GhcRn GhcRn
seg' = XParStmtBlock GhcRn GhcRn
-> [ExprLStmt GhcRn]
-> [IdP GhcRn]
-> SyntaxExpr GhcRn
-> ParStmtBlock GhcRn GhcRn
forall idL idR.
XParStmtBlock idL idR
-> [ExprLStmt idL]
-> [IdP idR]
-> SyntaxExpr idR
-> ParStmtBlock idL idR
ParStmtBlock XParStmtBlock GhcPs GhcPs
XParStmtBlock GhcRn GhcRn
x [ExprLStmt GhcRn]
stmts' [Name]
[IdP GhcRn]
used_bndrs SyntaxExpr GhcRn
return_op
           ; (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
-> RnM (([ParStmtBlock GhcRn GhcRn], thing), FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ((ParStmtBlock GhcRn GhcRn
seg'ParStmtBlock GhcRn GhcRn
-> [ParStmtBlock GhcRn GhcRn] -> [ParStmtBlock GhcRn GhcRn]
forall a. a -> [a] -> [a]
:[ParStmtBlock GhcRn GhcRn]
segs', thing
thing), FreeVars
fvs) }

    cmpByOcc :: Name -> Name -> Ordering
cmpByOcc Name
n1 Name
n2 = Name -> OccName
nameOccName Name
n1 OccName -> OccName -> Ordering
forall a. Ord a => a -> a -> Ordering
`compare` Name -> OccName
nameOccName Name
n2
    dupErr :: NonEmpty a -> IOEnv (Env TcGblEnv TcLclEnv) ()
dupErr NonEmpty a
vs = MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (String -> MsgDoc
text String
"Duplicate binding in parallel list comprehension for:"
                    MsgDoc -> MsgDoc -> MsgDoc
<+> MsgDoc -> MsgDoc
quotes (a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr (NonEmpty a -> a
forall a. NonEmpty a -> a
NE.head NonEmpty a
vs)))

lookupQualifiedDoStmtName :: HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
-- Like lookupStmtName, but respects QualifiedDo
lookupQualifiedDoStmtName :: HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
n
  = case HsStmtContext GhcRn -> Maybe ModuleName
forall p. HsStmtContext p -> Maybe ModuleName
qualifiedDoModuleName_maybe HsStmtContext GhcRn
ctxt of
      Maybe ModuleName
Nothing -> HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
n
      Just ModuleName
modName ->
        (Name -> SyntaxExprRn)
-> (Name, FreeVars) -> (SyntaxExprRn, FreeVars)
forall (a :: * -> * -> *) b c d.
Arrow a =>
a b c -> a (b, d) (c, d)
first (HsExpr GhcRn -> SyntaxExprRn
mkSyntaxExpr (HsExpr GhcRn -> SyntaxExprRn)
-> (Name -> HsExpr GhcRn) -> Name -> SyntaxExprRn
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Name -> HsExpr GhcRn
forall (id :: Pass). IdP (GhcPass id) -> HsExpr (GhcPass id)
nl_HsVar) ((Name, FreeVars) -> (SyntaxExprRn, FreeVars))
-> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Name
-> ModuleName -> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
lookupNameWithQualifier Name
n ModuleName
modName

lookupStmtName :: HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
-- Like lookupSyntax, but respects contexts
lookupStmtName :: HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupStmtName HsStmtContext GhcRn
ctxt Name
n
  | HsStmtContext GhcRn -> Bool
rebindableContext HsStmtContext GhcRn
ctxt
  = Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
n
  | Bool
otherwise
  = (SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (Name -> SyntaxExprRn
mkRnSyntaxExpr Name
n, FreeVars
emptyFVs)

lookupStmtNamePoly :: HsStmtContext GhcRn -> Name -> RnM (HsExpr GhcRn, FreeVars)
lookupStmtNamePoly :: HsStmtContext GhcRn -> Name -> TcM (HsExpr GhcRn, FreeVars)
lookupStmtNamePoly HsStmtContext GhcRn
ctxt Name
name
  | HsStmtContext GhcRn -> Bool
rebindableContext HsStmtContext GhcRn
ctxt
  = do { Bool
rebindable_on <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.RebindableSyntax
       ; if Bool
rebindable_on
         then do { Name
fm <- RdrName -> RnM Name
lookupOccRn (Name -> RdrName
nameRdrName Name
name)
                 ; (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XVar GhcRn -> Located (IdP GhcRn) -> HsExpr GhcRn
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar GhcRn
noExtField (Name -> Located Name
forall e. e -> Located e
noLoc Name
fm), Name -> FreeVars
unitFV Name
fm) }
         else TcM (HsExpr GhcRn, FreeVars)
not_rebindable }
  | Bool
otherwise
  = TcM (HsExpr GhcRn, FreeVars)
not_rebindable
  where
    not_rebindable :: TcM (HsExpr GhcRn, FreeVars)
not_rebindable = (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (XVar GhcRn -> Located (IdP GhcRn) -> HsExpr GhcRn
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar GhcRn
noExtField (Name -> Located Name
forall e. e -> Located e
noLoc Name
name), FreeVars
emptyFVs)

-- | Is this a context where we respect RebindableSyntax?
-- but ListComp are never rebindable
-- Neither is ArrowExpr, which has its own desugarer in GHC.HsToCore.Arrows
rebindableContext :: HsStmtContext GhcRn -> Bool
rebindableContext :: HsStmtContext GhcRn -> Bool
rebindableContext HsStmtContext GhcRn
ctxt = case HsStmtContext GhcRn
ctxt of
  HsStmtContext GhcRn
ListComp        -> Bool
False
  HsStmtContext GhcRn
ArrowExpr       -> Bool
False
  PatGuard {}     -> Bool
False

  DoExpr Maybe ModuleName
m        -> Maybe ModuleName -> Bool
forall a. Maybe a -> Bool
isNothing Maybe ModuleName
m
  MDoExpr Maybe ModuleName
m       -> Maybe ModuleName -> Bool
forall a. Maybe a -> Bool
isNothing Maybe ModuleName
m
  HsStmtContext GhcRn
MonadComp       -> Bool
True
  HsStmtContext GhcRn
GhciStmtCtxt    -> Bool
True   -- I suppose?

  ParStmtCtxt   HsStmtContext GhcRn
c -> HsStmtContext GhcRn -> Bool
rebindableContext HsStmtContext GhcRn
c     -- Look inside to
  TransStmtCtxt HsStmtContext GhcRn
c -> HsStmtContext GhcRn -> Bool
rebindableContext HsStmtContext GhcRn
c     -- the parent context

{-
Note [Renaming parallel Stmts]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Renaming parallel statements is painful.  Given, say
     [ a+c | a <- as, bs <- bss
           | c <- bs, a <- ds ]
Note that
  (a) In order to report "Defined but not used" about 'bs', we must
      rename each group of Stmts with a thing_inside whose FreeVars
      include at least {a,c}

  (b) We want to report that 'a' is illegally bound in both branches

  (c) The 'bs' in the second group must obviously not be captured by
      the binding in the first group

To satisfy (a) we nest the segements.
To satisfy (b) we check for duplicates just before thing_inside.
To satisfy (c) we reset the LocalRdrEnv each time.

************************************************************************
*                                                                      *
\subsubsection{mdo expressions}
*                                                                      *
************************************************************************
-}

type FwdRefs = NameSet
type Segment stmts = (Defs,
                      Uses,     -- May include defs
                      FwdRefs,  -- A subset of uses that are
                                --   (a) used before they are bound in this segment, or
                                --   (b) used here, and bound in subsequent segments
                      stmts)    -- Either Stmt or [Stmt]


-- wrapper that does both the left- and right-hand sides
rnRecStmtsAndThen :: Outputable (body GhcPs) =>
                     HsStmtContext GhcRn
                  -> (Located (body GhcPs)
                  -> RnM (Located (body GhcRn), FreeVars))
                  -> [LStmt GhcPs (Located (body GhcPs))]
                         -- assumes that the FreeVars returned includes
                         -- the FreeVars of the Segments
                  -> ([Segment (LStmt GhcRn (Located (body GhcRn)))]
                      -> RnM (a, FreeVars))
                  -> RnM (a, FreeVars)
rnRecStmtsAndThen :: forall (body :: * -> *) a.
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [LStmt GhcPs (Located (body GhcPs))]
-> ([Segment (LStmt GhcRn (Located (body GhcRn)))]
    -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnRecStmtsAndThen HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [LStmt GhcPs (Located (body GhcPs))]
s [Segment (LStmt GhcRn (Located (body GhcRn)))] -> RnM (a, FreeVars)
cont
  = do  { -- (A) Make the mini fixity env for all of the stmts
          MiniFixityEnv
fix_env <- [LFixitySig GhcPs] -> RnM MiniFixityEnv
makeMiniFixityEnv ([LStmt GhcPs (Located (body GhcPs))] -> [LFixitySig GhcPs]
forall body. [LStmtLR GhcPs GhcPs body] -> [LFixitySig GhcPs]
collectRecStmtsFixities [LStmt GhcPs (Located (body GhcPs))]
s)

          -- (B) Do the LHSes
        ; [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
new_lhs_and_fv <- MiniFixityEnv
-> [LStmt GhcPs (Located (body GhcPs))]
-> RnM [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
forall body.
Outputable body =>
MiniFixityEnv
-> [LStmt GhcPs body] -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmts_lhs MiniFixityEnv
fix_env [LStmt GhcPs (Located (body GhcPs))]
s

          --    ...bring them and their fixities into scope
        ; let bound_names :: [IdP GhcRn]
bound_names = [LStmtLR GhcRn GhcPs (Located (body GhcPs))] -> [IdP GhcRn]
forall (idL :: Pass) (idR :: Pass) body.
CollectPass (GhcPass idL) =>
[LStmtLR (GhcPass idL) (GhcPass idR) body] -> [IdP (GhcPass idL)]
collectLStmtsBinders (((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
 -> LStmtLR GhcRn GhcPs (Located (body GhcPs)))
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> [LStmtLR GhcRn GhcPs (Located (body GhcPs))]
forall a b. (a -> b) -> [a] -> [b]
map (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
-> LStmtLR GhcRn GhcPs (Located (body GhcPs))
forall a b. (a, b) -> a
fst [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
new_lhs_and_fv)
              -- Fake uses of variables introduced implicitly (warning suppression, see #4404)
              rec_uses :: [(SrcSpan, [Name])]
rec_uses = [LStmtLR GhcRn GhcPs (Located (body GhcPs))] -> [(SrcSpan, [Name])]
forall (idR :: Pass) (body :: * -> *).
[LStmtLR GhcRn (GhcPass idR) (Located (body (GhcPass idR)))]
-> [(SrcSpan, [Name])]
lStmtsImplicits (((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
 -> LStmtLR GhcRn GhcPs (Located (body GhcPs)))
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> [LStmtLR GhcRn GhcPs (Located (body GhcPs))]
forall a b. (a -> b) -> [a] -> [b]
map (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
-> LStmtLR GhcRn GhcPs (Located (body GhcPs))
forall a b. (a, b) -> a
fst [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
new_lhs_and_fv)
              implicit_uses :: FreeVars
implicit_uses = [Name] -> FreeVars
mkNameSet ([Name] -> FreeVars) -> [Name] -> FreeVars
forall a b. (a -> b) -> a -> b
$ ((SrcSpan, [Name]) -> [Name]) -> [(SrcSpan, [Name])] -> [Name]
forall (t :: * -> *) a b. Foldable t => (a -> [b]) -> t a -> [b]
concatMap (SrcSpan, [Name]) -> [Name]
forall a b. (a, b) -> b
snd ([(SrcSpan, [Name])] -> [Name]) -> [(SrcSpan, [Name])] -> [Name]
forall a b. (a -> b) -> a -> b
$ [(SrcSpan, [Name])]
rec_uses
        ; [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
forall a. [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
bindLocalNamesFV [Name]
[IdP GhcRn]
bound_names (RnM (a, FreeVars) -> RnM (a, FreeVars))
-> RnM (a, FreeVars) -> RnM (a, FreeVars)
forall a b. (a -> b) -> a -> b
$
          MiniFixityEnv -> [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
forall a. MiniFixityEnv -> [Name] -> RnM a -> RnM a
addLocalFixities MiniFixityEnv
fix_env [Name]
[IdP GhcRn]
bound_names (RnM (a, FreeVars) -> RnM (a, FreeVars))
-> RnM (a, FreeVars) -> RnM (a, FreeVars)
forall a b. (a -> b) -> a -> b
$ do

          -- (C) do the right-hand-sides and thing-inside
        { [Segment (LStmt GhcRn (Located (body GhcRn)))]
segs <- HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
rn_rec_stmts HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
[IdP GhcRn]
bound_names [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
new_lhs_and_fv
        ; (a
res, FreeVars
fvs) <- [Segment (LStmt GhcRn (Located (body GhcRn)))] -> RnM (a, FreeVars)
cont [Segment (LStmt GhcRn (Located (body GhcRn)))]
segs
        ; ((SrcSpan, [Name]) -> IOEnv (Env TcGblEnv TcLclEnv) ())
-> [(SrcSpan, [Name])] -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
mapM_ (\(SrcSpan
loc, [Name]
ns) -> SrcSpan
-> FreeVars -> Maybe [Name] -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkUnusedRecordWildcard SrcSpan
loc FreeVars
fvs ([Name] -> Maybe [Name]
forall a. a -> Maybe a
Just [Name]
ns))
                [(SrcSpan, [Name])]
rec_uses
        ; [Name] -> FreeVars -> IOEnv (Env TcGblEnv TcLclEnv) ()
warnUnusedLocalBinds [Name]
[IdP GhcRn]
bound_names (FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`unionNameSet` FreeVars
implicit_uses)
        ; (a, FreeVars) -> RnM (a, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (a
res, FreeVars
fvs) }}

-- get all the fixity decls in any Let stmt
collectRecStmtsFixities :: [LStmtLR GhcPs GhcPs body] -> [LFixitySig GhcPs]
collectRecStmtsFixities :: forall body. [LStmtLR GhcPs GhcPs body] -> [LFixitySig GhcPs]
collectRecStmtsFixities [LStmtLR GhcPs GhcPs body]
l =
    (LStmtLR GhcPs GhcPs body
 -> [LFixitySig GhcPs] -> [LFixitySig GhcPs])
-> [LFixitySig GhcPs]
-> [LStmtLR GhcPs GhcPs body]
-> [LFixitySig GhcPs]
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr (\ LStmtLR GhcPs GhcPs body
s -> \[LFixitySig GhcPs]
acc -> case LStmtLR GhcPs GhcPs body
s of
            (L SrcSpan
_ (LetStmt XLetStmt GhcPs GhcPs body
_ (L SrcSpan
_ (HsValBinds XHsValBinds GhcPs GhcPs
_ (ValBinds XValBinds GhcPs GhcPs
_ LHsBindsLR GhcPs GhcPs
_ [LSig GhcPs]
sigs))))) ->
              (LSig GhcPs -> [LFixitySig GhcPs] -> [LFixitySig GhcPs])
-> [LFixitySig GhcPs] -> [LSig GhcPs] -> [LFixitySig GhcPs]
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr (\ LSig GhcPs
sig -> \ [LFixitySig GhcPs]
acc -> case LSig GhcPs
sig of
                                         (L SrcSpan
loc (FixSig XFixSig GhcPs
_ FixitySig GhcPs
s)) -> (SrcSpan -> FixitySig GhcPs -> LFixitySig GhcPs
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc FixitySig GhcPs
s) LFixitySig GhcPs -> [LFixitySig GhcPs] -> [LFixitySig GhcPs]
forall a. a -> [a] -> [a]
: [LFixitySig GhcPs]
acc
                                         LSig GhcPs
_ -> [LFixitySig GhcPs]
acc) [LFixitySig GhcPs]
acc [LSig GhcPs]
sigs
            LStmtLR GhcPs GhcPs body
_ -> [LFixitySig GhcPs]
acc) [] [LStmtLR GhcPs GhcPs body]
l

-- left-hand sides

rn_rec_stmt_lhs :: Outputable body => MiniFixityEnv
                -> LStmt GhcPs body
                   -- rename LHS, and return its FVs
                   -- Warning: we will only need the FreeVars below in the case of a BindStmt,
                   -- so we don't bother to compute it accurately in the other cases
                -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]

rn_rec_stmt_lhs :: forall body.
Outputable body =>
MiniFixityEnv
-> LStmt GhcPs body -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmt_lhs MiniFixityEnv
_ (L SrcSpan
loc (BodyStmt XBodyStmt GhcPs GhcPs body
_ body
body SyntaxExpr GhcPs
a SyntaxExpr GhcPs
b))
  = [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall (m :: * -> *) a. Monad m => a -> m a
return [(SrcSpan
-> StmtLR GhcRn GhcPs body
-> GenLocated SrcSpan (StmtLR GhcRn GhcPs body)
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBodyStmt GhcRn GhcPs body
-> body
-> SyntaxExpr GhcPs
-> SyntaxExpr GhcPs
-> StmtLR GhcRn GhcPs body
forall idL idR body.
XBodyStmt idL idR body
-> body -> SyntaxExpr idR -> SyntaxExpr idR -> StmtLR idL idR body
BodyStmt NoExtField
XBodyStmt GhcRn GhcPs body
noExtField body
body SyntaxExpr GhcPs
a SyntaxExpr GhcPs
b), FreeVars
emptyFVs)]

rn_rec_stmt_lhs MiniFixityEnv
_ (L SrcSpan
loc (LastStmt XLastStmt GhcPs GhcPs body
_ body
body Maybe Bool
noret SyntaxExpr GhcPs
a))
  = [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall (m :: * -> *) a. Monad m => a -> m a
return [(SrcSpan
-> StmtLR GhcRn GhcPs body
-> GenLocated SrcSpan (StmtLR GhcRn GhcPs body)
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLastStmt GhcRn GhcPs body
-> body
-> Maybe Bool
-> SyntaxExpr GhcPs
-> StmtLR GhcRn GhcPs body
forall idL idR body.
XLastStmt idL idR body
-> body -> Maybe Bool -> SyntaxExpr idR -> StmtLR idL idR body
LastStmt NoExtField
XLastStmt GhcRn GhcPs body
noExtField body
body Maybe Bool
noret SyntaxExpr GhcPs
a), FreeVars
emptyFVs)]

rn_rec_stmt_lhs MiniFixityEnv
fix_env (L SrcSpan
loc (BindStmt XBindStmt GhcPs GhcPs body
_ LPat GhcPs
pat body
body))
  = do
      -- should the ctxt be MDo instead?
      (Located (Pat GhcRn)
pat', FreeVars
fv_pat) <- NameMaker -> LPat GhcPs -> RnM (LPat GhcRn, FreeVars)
rnBindPat (MiniFixityEnv -> NameMaker
localRecNameMaker MiniFixityEnv
fix_env) LPat GhcPs
pat
      [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall (m :: * -> *) a. Monad m => a -> m a
return [(SrcSpan
-> StmtLR GhcRn GhcPs body
-> GenLocated SrcSpan (StmtLR GhcRn GhcPs body)
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBindStmt GhcRn GhcPs body
-> LPat GhcRn -> body -> StmtLR GhcRn GhcPs body
forall idL idR body.
XBindStmt idL idR body -> LPat idL -> body -> StmtLR idL idR body
BindStmt NoExtField
XBindStmt GhcRn GhcPs body
noExtField Located (Pat GhcRn)
LPat GhcRn
pat' body
body), FreeVars
fv_pat)]

rn_rec_stmt_lhs MiniFixityEnv
_ (L SrcSpan
_ (LetStmt XLetStmt GhcPs GhcPs body
_ (L SrcSpan
_ binds :: HsLocalBinds GhcPs
binds@(HsIPBinds {}))))
  = MsgDoc
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall a. MsgDoc -> TcRn a
failWith (MsgDoc -> HsLocalBinds GhcPs -> MsgDoc
forall a. Outputable a => MsgDoc -> a -> MsgDoc
badIpBinds (String -> MsgDoc
text String
"an mdo expression") HsLocalBinds GhcPs
binds)

rn_rec_stmt_lhs MiniFixityEnv
fix_env (L SrcSpan
loc (LetStmt XLetStmt GhcPs GhcPs body
_ (L SrcSpan
l (HsValBinds XHsValBinds GhcPs GhcPs
x HsValBindsLR GhcPs GhcPs
binds))))
    = do ([Name]
_bound_names, HsValBindsLR GhcRn GhcPs
binds') <- MiniFixityEnv
-> HsValBindsLR GhcPs GhcPs
-> RnM ([Name], HsValBindsLR GhcRn GhcPs)
rnLocalValBindsLHS MiniFixityEnv
fix_env HsValBindsLR GhcPs GhcPs
binds
         [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall (m :: * -> *) a. Monad m => a -> m a
return [(SrcSpan
-> StmtLR GhcRn GhcPs body
-> GenLocated SrcSpan (StmtLR GhcRn GhcPs body)
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLetStmt GhcRn GhcPs body
-> LHsLocalBindsLR GhcRn GhcPs -> StmtLR GhcRn GhcPs body
forall idL idR body.
XLetStmt idL idR body
-> LHsLocalBindsLR idL idR -> StmtLR idL idR body
LetStmt NoExtField
XLetStmt GhcRn GhcPs body
noExtField (SrcSpan
-> HsLocalBindsLR GhcRn GhcPs -> LHsLocalBindsLR GhcRn GhcPs
forall l e. l -> e -> GenLocated l e
L SrcSpan
l (XHsValBinds GhcRn GhcPs
-> HsValBindsLR GhcRn GhcPs -> HsLocalBindsLR GhcRn GhcPs
forall idL idR.
XHsValBinds idL idR
-> HsValBindsLR idL idR -> HsLocalBindsLR idL idR
HsValBinds XHsValBinds GhcPs GhcPs
XHsValBinds GhcRn GhcPs
x HsValBindsLR GhcRn GhcPs
binds'))),
                 -- Warning: this is bogus; see function invariant
                 FreeVars
emptyFVs
                 )]

-- XXX Do we need to do something with the return and mfix names?
rn_rec_stmt_lhs MiniFixityEnv
fix_env (L SrcSpan
_ (RecStmt { recS_stmts :: forall idL idR body. StmtLR idL idR body -> [LStmtLR idL idR body]
recS_stmts = [LStmt GhcPs body]
stmts }))  -- Flatten Rec inside Rec
    = MiniFixityEnv
-> [LStmt GhcPs body]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall body.
Outputable body =>
MiniFixityEnv
-> [LStmt GhcPs body] -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmts_lhs MiniFixityEnv
fix_env [LStmt GhcPs body]
stmts

rn_rec_stmt_lhs MiniFixityEnv
_ stmt :: LStmt GhcPs body
stmt@(L SrcSpan
_ (ParStmt {}))       -- Syntactically illegal in mdo
  = String
-> MsgDoc
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt" (LStmt GhcPs body -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr LStmt GhcPs body
stmt)

rn_rec_stmt_lhs MiniFixityEnv
_ stmt :: LStmt GhcPs body
stmt@(L SrcSpan
_ (TransStmt {}))     -- Syntactically illegal in mdo
  = String
-> MsgDoc
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt" (LStmt GhcPs body -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr LStmt GhcPs body
stmt)

rn_rec_stmt_lhs MiniFixityEnv
_ stmt :: LStmt GhcPs body
stmt@(L SrcSpan
_ (ApplicativeStmt {})) -- Shouldn't appear yet
  = String
-> MsgDoc
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt" (LStmt GhcPs body -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr LStmt GhcPs body
stmt)

rn_rec_stmt_lhs MiniFixityEnv
_ (L SrcSpan
_ (LetStmt XLetStmt GhcPs GhcPs body
_ (L SrcSpan
_ (EmptyLocalBinds XEmptyLocalBinds GhcPs GhcPs
_))))
  = String
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [(GenLocated SrcSpan (StmtLR GhcRn GhcPs body), FreeVars)]
forall a. String -> a
panic String
"rn_rec_stmt LetStmt EmptyLocalBinds"

rn_rec_stmts_lhs :: Outputable body => MiniFixityEnv
                 -> [LStmt GhcPs body]
                 -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmts_lhs :: forall body.
Outputable body =>
MiniFixityEnv
-> [LStmt GhcPs body] -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmts_lhs MiniFixityEnv
fix_env [LStmt GhcPs body]
stmts
  = do { [(LStmtLR GhcRn GhcPs body, FreeVars)]
ls <- (LStmt GhcPs body -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)])
-> [LStmt GhcPs body] -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
forall (m :: * -> *) a b. Monad m => (a -> m [b]) -> [a] -> m [b]
concatMapM (MiniFixityEnv
-> LStmt GhcPs body -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
forall body.
Outputable body =>
MiniFixityEnv
-> LStmt GhcPs body -> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
rn_rec_stmt_lhs MiniFixityEnv
fix_env) [LStmt GhcPs body]
stmts
       ; let boundNames :: [IdP GhcRn]
boundNames = [LStmtLR GhcRn GhcPs body] -> [IdP GhcRn]
forall (idL :: Pass) (idR :: Pass) body.
CollectPass (GhcPass idL) =>
[LStmtLR (GhcPass idL) (GhcPass idR) body] -> [IdP (GhcPass idL)]
collectLStmtsBinders (((LStmtLR GhcRn GhcPs body, FreeVars) -> LStmtLR GhcRn GhcPs body)
-> [(LStmtLR GhcRn GhcPs body, FreeVars)]
-> [LStmtLR GhcRn GhcPs body]
forall a b. (a -> b) -> [a] -> [b]
map (LStmtLR GhcRn GhcPs body, FreeVars) -> LStmtLR GhcRn GhcPs body
forall a b. (a, b) -> a
fst [(LStmtLR GhcRn GhcPs body, FreeVars)]
ls)
            -- First do error checking: we need to check for dups here because we
            -- don't bind all of the variables from the Stmt at once
            -- with bindLocatedLocals.
       ; [Name] -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkDupNames [Name]
[IdP GhcRn]
boundNames
       ; [(LStmtLR GhcRn GhcPs body, FreeVars)]
-> RnM [(LStmtLR GhcRn GhcPs body, FreeVars)]
forall (m :: * -> *) a. Monad m => a -> m a
return [(LStmtLR GhcRn GhcPs body, FreeVars)]
ls }


-- right-hand-sides

rn_rec_stmt :: (Outputable (body GhcPs)) =>
               HsStmtContext GhcRn
            -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
            -> [Name]
            -> (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
            -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
        -- Rename a Stmt that is inside a RecStmt (or mdo)
        -- Assumes all binders are already in scope
        -- Turns each stmt into a singleton Stmt
rn_rec_stmt :: forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
rn_rec_stmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
_ (L SrcSpan
loc (LastStmt XLastStmt GhcRn GhcPs (Located (body GhcPs))
_ Located (body GhcPs)
body Maybe Bool
noret SyntaxExpr GhcPs
_), FreeVars
_)
  = do  { (Located (body GhcRn)
body', FreeVars
fv_expr) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
        ; (SyntaxExprRn
ret_op, FreeVars
fvs1)   <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
forall p.
HsStmtContext p -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDo HsStmtContext GhcRn
ctxt Name
returnMName
        ; [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (m :: * -> *) a. Monad m => a -> m a
return [(FreeVars
emptyNameSet, FreeVars
fv_expr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1, FreeVars
emptyNameSet,
                   SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLastStmt GhcRn GhcRn (Located (body GhcRn))
-> Located (body GhcRn)
-> Maybe Bool
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XLastStmt idL idR body
-> body -> Maybe Bool -> SyntaxExpr idR -> StmtLR idL idR body
LastStmt NoExtField
XLastStmt GhcRn GhcRn (Located (body GhcRn))
noExtField Located (body GhcRn)
body' Maybe Bool
noret SyntaxExpr GhcRn
SyntaxExprRn
ret_op))] }

rn_rec_stmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
_ (L SrcSpan
loc (BodyStmt XBodyStmt GhcRn GhcPs (Located (body GhcPs))
_ Located (body GhcPs)
body SyntaxExpr GhcPs
_ SyntaxExpr GhcPs
_), FreeVars
_)
  = do { (Located (body GhcRn)
body', FreeVars
fvs) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
       ; (SyntaxExprRn
then_op, FreeVars
fvs1) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
forall p.
HsStmtContext p -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDo HsStmtContext GhcRn
ctxt Name
thenMName
       ; [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (m :: * -> *) a. Monad m => a -> m a
return [(FreeVars
emptyNameSet, FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1, FreeVars
emptyNameSet,
                 SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBodyStmt GhcRn GhcRn (Located (body GhcRn))
-> Located (body GhcRn)
-> SyntaxExpr GhcRn
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XBodyStmt idL idR body
-> body -> SyntaxExpr idR -> SyntaxExpr idR -> StmtLR idL idR body
BodyStmt NoExtField
XBodyStmt GhcRn GhcRn (Located (body GhcRn))
noExtField Located (body GhcRn)
body' SyntaxExpr GhcRn
SyntaxExprRn
then_op SyntaxExpr GhcRn
forall (p :: Pass). IsPass p => SyntaxExpr (GhcPass p)
noSyntaxExpr))] }

rn_rec_stmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
_ (L SrcSpan
loc (BindStmt XBindStmt GhcRn GhcPs (Located (body GhcPs))
_ LPat GhcRn
pat' Located (body GhcPs)
body), FreeVars
fv_pat)
  = do { (Located (body GhcRn)
body', FreeVars
fv_expr) <- Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody Located (body GhcPs)
body
       ; (SyntaxExprRn
bind_op, FreeVars
fvs1) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
forall p.
HsStmtContext p -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDo HsStmtContext GhcRn
ctxt Name
bindMName

       ; (Maybe SyntaxExprRn
fail_op, FreeVars
fvs2) <- HsStmtContext GhcRn -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
forall p.
HsStmtContext p -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
getMonadFailOp HsStmtContext GhcRn
ctxt

       ; let bndrs :: FreeVars
bndrs = [Name] -> FreeVars
mkNameSet (LPat GhcRn -> [IdP GhcRn]
forall p. CollectPass p => LPat p -> [IdP p]
collectPatBinders LPat GhcRn
pat')
             fvs :: FreeVars
fvs   = FreeVars
fv_expr FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fv_pat FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2
       ; let xbsrn :: XBindStmtRn
xbsrn = XBindStmtRn :: SyntaxExpr GhcRn -> Maybe (SyntaxExpr GhcRn) -> XBindStmtRn
XBindStmtRn { xbsrn_bindOp :: SyntaxExpr GhcRn
xbsrn_bindOp = SyntaxExpr GhcRn
SyntaxExprRn
bind_op, xbsrn_failOp :: Maybe (SyntaxExpr GhcRn)
xbsrn_failOp = Maybe (SyntaxExpr GhcRn)
Maybe SyntaxExprRn
fail_op }
       ; [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (m :: * -> *) a. Monad m => a -> m a
return [(FreeVars
bndrs, FreeVars
fvs, FreeVars
bndrs FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
fvs,
                  SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XBindStmt GhcRn GhcRn (Located (body GhcRn))
-> LPat GhcRn
-> Located (body GhcRn)
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XBindStmt idL idR body -> LPat idL -> body -> StmtLR idL idR body
BindStmt XBindStmt GhcRn GhcRn (Located (body GhcRn))
XBindStmtRn
xbsrn LPat GhcRn
pat' Located (body GhcRn)
body'))] }

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ (L SrcSpan
_ (LetStmt XLetStmt GhcRn GhcPs (Located (body GhcPs))
_ (L SrcSpan
_ binds :: HsLocalBindsLR GhcRn GhcPs
binds@(HsIPBinds {}))), FreeVars
_)
  = MsgDoc -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. MsgDoc -> TcRn a
failWith (MsgDoc -> HsLocalBindsLR GhcRn GhcPs -> MsgDoc
forall a. Outputable a => MsgDoc -> a -> MsgDoc
badIpBinds (String -> MsgDoc
text String
"an mdo expression") HsLocalBindsLR GhcRn GhcPs
binds)

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
all_bndrs (L SrcSpan
loc (LetStmt XLetStmt GhcRn GhcPs (Located (body GhcPs))
_ (L SrcSpan
l (HsValBinds XHsValBinds GhcRn GhcPs
x HsValBindsLR GhcRn GhcPs
binds'))), FreeVars
_)
  = do { (HsValBinds GhcRn
binds', DefUses
du_binds) <- FreeVars
-> HsValBindsLR GhcRn GhcPs -> RnM (HsValBinds GhcRn, DefUses)
rnLocalValBindsRHS ([Name] -> FreeVars
mkNameSet [Name]
all_bndrs) HsValBindsLR GhcRn GhcPs
binds'
           -- fixities and unused are handled above in rnRecStmtsAndThen
       ; let fvs :: FreeVars
fvs = DefUses -> FreeVars
allUses DefUses
du_binds
       ; [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (m :: * -> *) a. Monad m => a -> m a
return [(DefUses -> FreeVars
duDefs DefUses
du_binds, FreeVars
fvs, FreeVars
emptyNameSet,
                 SrcSpan
-> StmtLR GhcRn GhcRn (Located (body GhcRn))
-> LStmt GhcRn (Located (body GhcRn))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLetStmt GhcRn GhcRn (Located (body GhcRn))
-> LHsLocalBinds GhcRn -> StmtLR GhcRn GhcRn (Located (body GhcRn))
forall idL idR body.
XLetStmt idL idR body
-> LHsLocalBindsLR idL idR -> StmtLR idL idR body
LetStmt NoExtField
XLetStmt GhcRn GhcRn (Located (body GhcRn))
noExtField (SrcSpan -> HsLocalBinds GhcRn -> LHsLocalBinds GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
l (XHsValBinds GhcRn GhcRn -> HsValBinds GhcRn -> HsLocalBinds GhcRn
forall idL idR.
XHsValBinds idL idR
-> HsValBindsLR idL idR -> HsLocalBindsLR idL idR
HsValBinds XHsValBinds GhcRn GhcPs
XHsValBinds GhcRn GhcRn
x HsValBinds GhcRn
binds'))))] }

-- no RecStmt case because they get flattened above when doing the LHSes
rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ stmt :: (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt@(L SrcSpan
_ (RecStmt {}), FreeVars
_)
  = String
-> MsgDoc -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt: RecStmt" ((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt)

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ stmt :: (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt@(L SrcSpan
_ (ParStmt {}), FreeVars
_)       -- Syntactically illegal in mdo
  = String
-> MsgDoc -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt: ParStmt" ((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt)

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ stmt :: (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt@(L SrcSpan
_ (TransStmt {}), FreeVars
_)     -- Syntactically illegal in mdo
  = String
-> MsgDoc -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt: TransStmt" ((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt)

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ (L SrcSpan
_ (LetStmt XLetStmt GhcRn GhcPs (Located (body GhcPs))
_ (L SrcSpan
_ (EmptyLocalBinds XEmptyLocalBinds GhcRn GhcPs
_))), FreeVars
_)
  = String -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. String -> a
panic String
"rn_rec_stmt: LetStmt EmptyLocalBinds"

rn_rec_stmt HsStmtContext GhcRn
_ Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
_ [Name]
_ stmt :: (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt@(L SrcSpan
_ (ApplicativeStmt {}), FreeVars
_)
  = String
-> MsgDoc -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"rn_rec_stmt: ApplicativeStmt" ((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
stmt)

rn_rec_stmts :: Outputable (body GhcPs) =>
                HsStmtContext GhcRn
             -> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
             -> [Name]
             -> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
             -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
rn_rec_stmts :: forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
rn_rec_stmts HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
bndrs [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
stmts
  = do { [[Segment (LStmt GhcRn (Located (body GhcRn)))]]
segs_s <- ((LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
 -> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))])
-> [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [[Segment (LStmt GhcRn (Located (body GhcRn)))]]
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM (HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> (Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars))
-> [Name]
-> (LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
rn_rec_stmt HsStmtContext GhcRn
ctxt Located (body GhcPs) -> RnM (Located (body GhcRn), FreeVars)
rnBody [Name]
bndrs) [(LStmtLR GhcRn GhcPs (Located (body GhcPs)), FreeVars)]
stmts
       ; [Segment (LStmt GhcRn (Located (body GhcRn)))]
-> RnM [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (m :: * -> *) a. Monad m => a -> m a
return ([[Segment (LStmt GhcRn (Located (body GhcRn)))]]
-> [Segment (LStmt GhcRn (Located (body GhcRn)))]
forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat [[Segment (LStmt GhcRn (Located (body GhcRn)))]]
segs_s) }

---------------------------------------------
segmentRecStmts :: SrcSpan -> HsStmtContext GhcRn
                -> Stmt GhcRn body
                -> [Segment (LStmt GhcRn body)] -> FreeVars
                -> ([LStmt GhcRn body], FreeVars)

segmentRecStmts :: forall body.
SrcSpan
-> HsStmtContext GhcRn
-> Stmt GhcRn body
-> [Segment (LStmt GhcRn body)]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
segmentRecStmts SrcSpan
loc HsStmtContext GhcRn
ctxt Stmt GhcRn body
empty_rec_stmt [Segment (LStmt GhcRn body)]
segs FreeVars
fvs_later
  | [Segment (LStmt GhcRn body)] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [Segment (LStmt GhcRn body)]
segs
  = ([], FreeVars
fvs_later)

  | MDoExpr Maybe ModuleName
_ <- HsStmtContext GhcRn
ctxt
  = Stmt GhcRn body
-> [Segment [LStmt GhcRn body]]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
forall body.
Stmt GhcRn body
-> [Segment [LStmt GhcRn body]]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
segsToStmts Stmt GhcRn body
empty_rec_stmt [Segment [LStmt GhcRn body]]
grouped_segs FreeVars
fvs_later
               -- Step 4: Turn the segments into Stmts
                --         Use RecStmt when and only when there are fwd refs
                --         Also gather up the uses from the end towards the
                --         start, so we can tell the RecStmt which things are
                --         used 'after' the RecStmt

  | Bool
otherwise
  = ([ SrcSpan -> Stmt GhcRn body -> LStmt GhcRn body
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (Stmt GhcRn body -> LStmt GhcRn body)
-> Stmt GhcRn body -> LStmt GhcRn body
forall a b. (a -> b) -> a -> b
$
       Stmt GhcRn body
empty_rec_stmt { recS_stmts :: [LStmt GhcRn body]
recS_stmts = [LStmt GhcRn body]
ss
                      , recS_later_ids :: [IdP GhcRn]
recS_later_ids = FreeVars -> [Name]
nameSetElemsStable
                                           (FreeVars
defs FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
fvs_later)
                      , recS_rec_ids :: [IdP GhcRn]
recS_rec_ids   = FreeVars -> [Name]
nameSetElemsStable
                                           (FreeVars
defs FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
uses) }]
          -- See Note [Deterministic ApplicativeDo and RecursiveDo desugaring]
    , FreeVars
uses FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs_later)

  where
    ([FreeVars]
defs_s, [FreeVars]
uses_s, [FreeVars]
_, [LStmt GhcRn body]
ss) = [Segment (LStmt GhcRn body)]
-> ([FreeVars], [FreeVars], [FreeVars], [LStmt GhcRn body])
forall a b c d. [(a, b, c, d)] -> ([a], [b], [c], [d])
unzip4 [Segment (LStmt GhcRn body)]
segs
    defs :: FreeVars
defs = [FreeVars] -> FreeVars
plusFVs [FreeVars]
defs_s
    uses :: FreeVars
uses = [FreeVars] -> FreeVars
plusFVs [FreeVars]
uses_s

                -- Step 2: Fill in the fwd refs.
                --         The segments are all singletons, but their fwd-ref
                --         field mentions all the things used by the segment
                --         that are bound after their use
    segs_w_fwd_refs :: [Segment (LStmt GhcRn body)]
segs_w_fwd_refs = [Segment (LStmt GhcRn body)] -> [Segment (LStmt GhcRn body)]
forall a. [Segment a] -> [Segment a]
addFwdRefs [Segment (LStmt GhcRn body)]
segs

                -- Step 3: Group together the segments to make bigger segments
                --         Invariant: in the result, no segment uses a variable
                --                    bound in a later segment
    grouped_segs :: [Segment [LStmt GhcRn body]]
grouped_segs = HsStmtContext GhcRn
-> [Segment (LStmt GhcRn body)] -> [Segment [LStmt GhcRn body]]
forall body.
HsStmtContext GhcRn
-> [Segment (LStmt GhcRn body)] -> [Segment [LStmt GhcRn body]]
glomSegments HsStmtContext GhcRn
ctxt [Segment (LStmt GhcRn body)]
segs_w_fwd_refs

----------------------------
addFwdRefs :: [Segment a] -> [Segment a]
-- So far the segments only have forward refs *within* the Stmt
--      (which happens for bind:  x <- ...x...)
-- This function adds the cross-seg fwd ref info

addFwdRefs :: forall a. [Segment a] -> [Segment a]
addFwdRefs [Segment a]
segs
  = ([Segment a], FreeVars) -> [Segment a]
forall a b. (a, b) -> a
fst ((Segment a -> ([Segment a], FreeVars) -> ([Segment a], FreeVars))
-> ([Segment a], FreeVars)
-> [Segment a]
-> ([Segment a], FreeVars)
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr Segment a -> ([Segment a], FreeVars) -> ([Segment a], FreeVars)
forall {d}.
(FreeVars, FreeVars, FreeVars, d)
-> ([(FreeVars, FreeVars, FreeVars, d)], FreeVars)
-> ([(FreeVars, FreeVars, FreeVars, d)], FreeVars)
mk_seg ([], FreeVars
emptyNameSet) [Segment a]
segs)
  where
    mk_seg :: (FreeVars, FreeVars, FreeVars, d)
-> ([(FreeVars, FreeVars, FreeVars, d)], FreeVars)
-> ([(FreeVars, FreeVars, FreeVars, d)], FreeVars)
mk_seg (FreeVars
defs, FreeVars
uses, FreeVars
fwds, d
stmts) ([(FreeVars, FreeVars, FreeVars, d)]
segs, FreeVars
later_defs)
        = ((FreeVars, FreeVars, FreeVars, d)
new_seg (FreeVars, FreeVars, FreeVars, d)
-> [(FreeVars, FreeVars, FreeVars, d)]
-> [(FreeVars, FreeVars, FreeVars, d)]
forall a. a -> [a] -> [a]
: [(FreeVars, FreeVars, FreeVars, d)]
segs, FreeVars
all_defs)
        where
          new_seg :: (FreeVars, FreeVars, FreeVars, d)
new_seg = (FreeVars
defs, FreeVars
uses, FreeVars
new_fwds, d
stmts)
          all_defs :: FreeVars
all_defs = FreeVars
later_defs FreeVars -> FreeVars -> FreeVars
`unionNameSet` FreeVars
defs
          new_fwds :: FreeVars
new_fwds = FreeVars
fwds FreeVars -> FreeVars -> FreeVars
`unionNameSet` (FreeVars
uses FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
later_defs)
                -- Add the downstream fwd refs here

{-
Note [Segmenting mdo]
~~~~~~~~~~~~~~~~~~~~~
NB. June 7 2012: We only glom segments that appear in an explicit mdo;
and leave those found in "do rec"'s intact.  See
https://gitlab.haskell.org/ghc/ghc/issues/4148 for the discussion
leading to this design choice.  Hence the test in segmentRecStmts.

Note [Glomming segments]
~~~~~~~~~~~~~~~~~~~~~~~~
Glomming the singleton segments of an mdo into minimal recursive groups.

At first I thought this was just strongly connected components, but
there's an important constraint: the order of the stmts must not change.

Consider
     mdo { x <- ...y...
           p <- z
           y <- ...x...
           q <- x
           z <- y
           r <- x }

Here, the first stmt mention 'y', which is bound in the third.
But that means that the innocent second stmt (p <- z) gets caught
up in the recursion.  And that in turn means that the binding for
'z' has to be included... and so on.

Start at the tail { r <- x }
Now add the next one { z <- y ; r <- x }
Now add one more     { q <- x ; z <- y ; r <- x }
Now one more... but this time we have to group a bunch into rec
     { rec { y <- ...x... ; q <- x ; z <- y } ; r <- x }
Now one more, which we can add on without a rec
     { p <- z ;
       rec { y <- ...x... ; q <- x ; z <- y } ;
       r <- x }
Finally we add the last one; since it mentions y we have to
glom it together with the first two groups
     { rec { x <- ...y...; p <- z ; y <- ...x... ;
             q <- x ; z <- y } ;
       r <- x }
-}

glomSegments :: HsStmtContext GhcRn
             -> [Segment (LStmt GhcRn body)]
             -> [Segment [LStmt GhcRn body]]
                                  -- Each segment has a non-empty list of Stmts
-- See Note [Glomming segments]

glomSegments :: forall body.
HsStmtContext GhcRn
-> [Segment (LStmt GhcRn body)] -> [Segment [LStmt GhcRn body]]
glomSegments HsStmtContext GhcRn
_ [] = []
glomSegments HsStmtContext GhcRn
ctxt ((FreeVars
defs,FreeVars
uses,FreeVars
fwds,LStmt GhcRn body
stmt) : [Segment (LStmt GhcRn body)]
segs)
        -- Actually stmts will always be a singleton
  = (FreeVars
seg_defs, FreeVars
seg_uses, FreeVars
seg_fwds, [LStmt GhcRn body]
seg_stmts)  Segment [LStmt GhcRn body]
-> [Segment [LStmt GhcRn body]] -> [Segment [LStmt GhcRn body]]
forall a. a -> [a] -> [a]
: [Segment [LStmt GhcRn body]]
others
  where
    segs' :: [Segment [LStmt GhcRn body]]
segs'            = HsStmtContext GhcRn
-> [Segment (LStmt GhcRn body)] -> [Segment [LStmt GhcRn body]]
forall body.
HsStmtContext GhcRn
-> [Segment (LStmt GhcRn body)] -> [Segment [LStmt GhcRn body]]
glomSegments HsStmtContext GhcRn
ctxt [Segment (LStmt GhcRn body)]
segs
    ([Segment [LStmt GhcRn body]]
extras, [Segment [LStmt GhcRn body]]
others) = FreeVars
-> [Segment [LStmt GhcRn body]]
-> ([Segment [LStmt GhcRn body]], [Segment [LStmt GhcRn body]])
forall a. FreeVars -> [Segment a] -> ([Segment a], [Segment a])
grab FreeVars
uses [Segment [LStmt GhcRn body]]
segs'
    ([FreeVars]
ds, [FreeVars]
us, [FreeVars]
fs, [[LStmt GhcRn body]]
ss) = [Segment [LStmt GhcRn body]]
-> ([FreeVars], [FreeVars], [FreeVars], [[LStmt GhcRn body]])
forall a b c d. [(a, b, c, d)] -> ([a], [b], [c], [d])
unzip4 [Segment [LStmt GhcRn body]]
extras

    seg_defs :: FreeVars
seg_defs  = [FreeVars] -> FreeVars
plusFVs [FreeVars]
ds FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
defs
    seg_uses :: FreeVars
seg_uses  = [FreeVars] -> FreeVars
plusFVs [FreeVars]
us FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
uses
    seg_fwds :: FreeVars
seg_fwds  = [FreeVars] -> FreeVars
plusFVs [FreeVars]
fs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fwds
    seg_stmts :: [LStmt GhcRn body]
seg_stmts = LStmt GhcRn body
stmt LStmt GhcRn body -> [LStmt GhcRn body] -> [LStmt GhcRn body]
forall a. a -> [a] -> [a]
: [[LStmt GhcRn body]] -> [LStmt GhcRn body]
forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat [[LStmt GhcRn body]]
ss

    grab :: NameSet             -- The client
         -> [Segment a]
         -> ([Segment a],       -- Needed by the 'client'
             [Segment a])       -- Not needed by the client
        -- The result is simply a split of the input
    grab :: forall a. FreeVars -> [Segment a] -> ([Segment a], [Segment a])
grab FreeVars
uses [Segment a]
dus
        = ([Segment a] -> [Segment a]
forall a. [a] -> [a]
reverse [Segment a]
yeses, [Segment a] -> [Segment a]
forall a. [a] -> [a]
reverse [Segment a]
noes)
        where
          ([Segment a]
noes, [Segment a]
yeses)           = (Segment a -> Bool) -> [Segment a] -> ([Segment a], [Segment a])
forall a. (a -> Bool) -> [a] -> ([a], [a])
span Segment a -> Bool
not_needed ([Segment a] -> [Segment a]
forall a. [a] -> [a]
reverse [Segment a]
dus)
          not_needed :: Segment a -> Bool
not_needed (FreeVars
defs,FreeVars
_,FreeVars
_,a
_) = FreeVars -> FreeVars -> Bool
disjointNameSet FreeVars
defs FreeVars
uses

----------------------------------------------------
segsToStmts :: Stmt GhcRn body
                                  -- A RecStmt with the SyntaxOps filled in
            -> [Segment [LStmt GhcRn body]]
                                  -- Each Segment has a non-empty list of Stmts
            -> FreeVars           -- Free vars used 'later'
            -> ([LStmt GhcRn body], FreeVars)

segsToStmts :: forall body.
Stmt GhcRn body
-> [Segment [LStmt GhcRn body]]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
segsToStmts Stmt GhcRn body
_ [] FreeVars
fvs_later = ([], FreeVars
fvs_later)
segsToStmts Stmt GhcRn body
empty_rec_stmt ((FreeVars
defs, FreeVars
uses, FreeVars
fwds, [LStmt GhcRn body]
ss) : [Segment [LStmt GhcRn body]]
segs) FreeVars
fvs_later
  = ASSERT( not (null ss) )
    (LStmt GhcRn body
new_stmt LStmt GhcRn body -> [LStmt GhcRn body] -> [LStmt GhcRn body]
forall a. a -> [a] -> [a]
: [LStmt GhcRn body]
later_stmts, FreeVars
later_uses FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
uses)
  where
    ([LStmt GhcRn body]
later_stmts, FreeVars
later_uses) = Stmt GhcRn body
-> [Segment [LStmt GhcRn body]]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
forall body.
Stmt GhcRn body
-> [Segment [LStmt GhcRn body]]
-> FreeVars
-> ([LStmt GhcRn body], FreeVars)
segsToStmts Stmt GhcRn body
empty_rec_stmt [Segment [LStmt GhcRn body]]
segs FreeVars
fvs_later
    new_stmt :: LStmt GhcRn body
new_stmt | Bool
non_rec   = [LStmt GhcRn body] -> LStmt GhcRn body
forall a. [a] -> a
head [LStmt GhcRn body]
ss
             | Bool
otherwise = SrcSpan -> Stmt GhcRn body -> LStmt GhcRn body
forall l e. l -> e -> GenLocated l e
L (LStmt GhcRn body -> SrcSpan
forall l e. GenLocated l e -> l
getLoc ([LStmt GhcRn body] -> LStmt GhcRn body
forall a. [a] -> a
head [LStmt GhcRn body]
ss)) Stmt GhcRn body
rec_stmt
    rec_stmt :: Stmt GhcRn body
rec_stmt = Stmt GhcRn body
empty_rec_stmt { recS_stmts :: [LStmt GhcRn body]
recS_stmts     = [LStmt GhcRn body]
ss
                              , recS_later_ids :: [IdP GhcRn]
recS_later_ids = FreeVars -> [Name]
nameSetElemsStable FreeVars
used_later
                              , recS_rec_ids :: [IdP GhcRn]
recS_rec_ids   = FreeVars -> [Name]
nameSetElemsStable FreeVars
fwds }
          -- See Note [Deterministic ApplicativeDo and RecursiveDo desugaring]
    non_rec :: Bool
non_rec    = [LStmt GhcRn body] -> Bool
forall a. [a] -> Bool
isSingleton [LStmt GhcRn body]
ss Bool -> Bool -> Bool
&& FreeVars -> Bool
isEmptyNameSet FreeVars
fwds
    used_later :: FreeVars
used_later = FreeVars
defs FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
later_uses
                                -- The ones needed after the RecStmt

{-
************************************************************************
*                                                                      *
ApplicativeDo
*                                                                      *
************************************************************************

Note [ApplicativeDo]

= Example =

For a sequence of statements

 do
     x <- A
     y <- B x
     z <- C
     return (f x y z)

We want to transform this to

  (\(x,y) z -> f x y z) <$> (do x <- A; y <- B x; return (x,y)) <*> C

It would be easy to notice that "y <- B x" and "z <- C" are
independent and do something like this:

 do
     x <- A
     (y,z) <- (,) <$> B x <*> C
     return (f x y z)

But this isn't enough! A and C were also independent, and this
transformation loses the ability to do A and C in parallel.

The algorithm works by first splitting the sequence of statements into
independent "segments", and a separate "tail" (the final statement). In
our example above, the segements would be

     [ x <- A
     , y <- B x ]

     [ z <- C ]

and the tail is:

     return (f x y z)

Then we take these segments and make an Applicative expression from them:

     (\(x,y) z -> return (f x y z))
       <$> do { x <- A; y <- B x; return (x,y) }
       <*> C

Finally, we recursively apply the transformation to each segment, to
discover any nested parallelism.

= Syntax & spec =

  expr ::= ... | do {stmt_1; ..; stmt_n} expr | ...

  stmt ::= pat <- expr
         | (arg_1 | ... | arg_n)  -- applicative composition, n>=1
         | ...                    -- other kinds of statement (e.g. let)

  arg ::= pat <- expr
        | {stmt_1; ..; stmt_n} {var_1..var_n}

(note that in the actual implementation,the expr in a do statement is
represented by a LastStmt as the final stmt, this is just a
representational issue and may change later.)

== Transformation to introduce applicative stmts ==

ado {} tail = tail
ado {pat <- expr} {return expr'} = (mkArg(pat <- expr)); return expr'
ado {one} tail = one : tail
ado stmts tail
  | n == 1 = ado before (ado after tail)
    where (before,after) = split(stmts_1)
  | n > 1  = (mkArg(stmts_1) | ... | mkArg(stmts_n)); tail
  where
    {stmts_1 .. stmts_n} = segments(stmts)

segments(stmts) =
  -- divide stmts into segments with no interdependencies

mkArg({pat <- expr}) = (pat <- expr)
mkArg({stmt_1; ...; stmt_n}) =
  {stmt_1; ...; stmt_n} {vars(stmt_1) u .. u vars(stmt_n)}

split({stmt_1; ..; stmt_n) =
  ({stmt_1; ..; stmt_i}, {stmt_i+1; ..; stmt_n})
  -- 1 <= i <= n
  -- i is a good place to insert a bind

== Desugaring for do ==

dsDo {} expr = expr

dsDo {pat <- rhs; stmts} expr =
   rhs >>= \pat -> dsDo stmts expr

dsDo {(arg_1 | ... | arg_n)} (return expr) =
  (\argpat (arg_1) .. argpat(arg_n) -> expr)
     <$> argexpr(arg_1)
     <*> ...
     <*> argexpr(arg_n)

dsDo {(arg_1 | ... | arg_n); stmts} expr =
  join (\argpat (arg_1) .. argpat(arg_n) -> dsDo stmts expr)
     <$> argexpr(arg_1)
     <*> ...
     <*> argexpr(arg_n)

= Relevant modules in the rest of the compiler =

ApplicativeDo touches a few phases in the compiler:

* Renamer: The journey begins here in the renamer, where do-blocks are
  scheduled as outlined above and transformed into applicative
  combinators.  However, the code is still represented as a do-block
  with special forms of applicative statements. This allows us to
  recover the original do-block when e.g. printing type errors, where
  we don't want to show any of the applicative combinators since they
  don't exist in the source code.
  See ApplicativeStmt and ApplicativeArg in HsExpr.

* Typechecker: ApplicativeDo passes through the typechecker much like any
  other form of expression. The only crux is that the typechecker has to
  be aware of the special ApplicativeDo statements in the do-notation, and
  typecheck them appropriately.
  Relevant module: GHC.Tc.Gen.Match

* Desugarer: Any do-block which contains applicative statements is desugared
  as outlined above, to use the Applicative combinators.
  Relevant module: GHC.HsToCore.Expr

-}

-- | The 'Name's of @return@ and @pure@. These may not be 'returnName' and
-- 'pureName' due to @QualifiedDo@ or @RebindableSyntax@.
data MonadNames = MonadNames { MonadNames -> Name
return_name, MonadNames -> Name
pure_name :: Name }

instance Outputable MonadNames where
  ppr :: MonadNames -> MsgDoc
ppr (MonadNames {return_name :: MonadNames -> Name
return_name=Name
return_name,pure_name :: MonadNames -> Name
pure_name=Name
pure_name}) =
    [MsgDoc] -> MsgDoc
hcat
    [String -> MsgDoc
text String
"MonadNames { return_name = "
    ,Name -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr Name
return_name
    ,String -> MsgDoc
text String
", pure_name = "
    ,Name -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr Name
pure_name
    ,String -> MsgDoc
text String
"}"
    ]

-- | rearrange a list of statements using ApplicativeDoStmt.  See
-- Note [ApplicativeDo].
rearrangeForApplicativeDo
  :: HsStmtContext GhcRn
  -> [(ExprLStmt GhcRn, FreeVars)]
  -> RnM ([ExprLStmt GhcRn], FreeVars)

rearrangeForApplicativeDo :: HsStmtContext GhcRn
-> [(ExprLStmt GhcRn, FreeVars)]
-> RnM ([ExprLStmt GhcRn], FreeVars)
rearrangeForApplicativeDo HsStmtContext GhcRn
_ [] = ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([], FreeVars
emptyNameSet)
rearrangeForApplicativeDo HsStmtContext GhcRn
_ [(ExprLStmt GhcRn
one,FreeVars
_)] = ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([ExprLStmt GhcRn
one], FreeVars
emptyNameSet)
rearrangeForApplicativeDo HsStmtContext GhcRn
ctxt [(ExprLStmt GhcRn, FreeVars)]
stmts0 = do
  Bool
optimal_ado <- GeneralFlag -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. GeneralFlag -> TcRnIf gbl lcl Bool
goptM GeneralFlag
Opt_OptimalApplicativeDo
  let stmt_tree :: ExprStmtTree
stmt_tree | Bool
optimal_ado = [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeOptimal [(ExprLStmt GhcRn, FreeVars)]
stmts
                | Bool
otherwise = [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeHeuristic [(ExprLStmt GhcRn, FreeVars)]
stmts
  String -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
traceRn String
"rearrangeForADo" (ExprStmtTree -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr ExprStmtTree
stmt_tree)
  (Name
return_name, FreeVars
_) <- HsStmtContext GhcRn
-> Name -> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
forall p.
HsStmtContext p
-> Name -> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
lookupQualifiedDoName HsStmtContext GhcRn
ctxt Name
returnMName
  (Name
pure_name, FreeVars
_)   <- HsStmtContext GhcRn
-> Name -> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
forall p.
HsStmtContext p
-> Name -> IOEnv (Env TcGblEnv TcLclEnv) (Name, FreeVars)
lookupQualifiedDoName HsStmtContext GhcRn
ctxt Name
pureAName
  let monad_names :: MonadNames
monad_names = MonadNames :: Name -> Name -> MonadNames
MonadNames { return_name :: Name
return_name = Name
return_name
                               , pure_name :: Name
pure_name   = Name
pure_name }
  MonadNames
-> HsStmtContext GhcRn
-> ExprStmtTree
-> [ExprLStmt GhcRn]
-> FreeVars
-> RnM ([ExprLStmt GhcRn], FreeVars)
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt ExprStmtTree
stmt_tree [ExprLStmt GhcRn
last] FreeVars
last_fvs
  where
    ([(ExprLStmt GhcRn, FreeVars)]
stmts,(ExprLStmt GhcRn
last,FreeVars
last_fvs)) = [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], (ExprLStmt GhcRn, FreeVars))
forall {a}. [a] -> ([a], a)
findLast [(ExprLStmt GhcRn, FreeVars)]
stmts0
    findLast :: [a] -> ([a], a)
findLast [] = String -> ([a], a)
forall a. HasCallStack => String -> a
error String
"findLast"
    findLast [a
last] = ([],a
last)
    findLast (a
x:[a]
xs) = (a
xa -> [a] -> [a]
forall a. a -> [a] -> [a]
:[a]
rest,a
last) where ([a]
rest,a
last) = [a] -> ([a], a)
findLast [a]
xs

-- | A tree of statements using a mixture of applicative and bind constructs.
data StmtTree a
  = StmtTreeOne a
  | StmtTreeBind (StmtTree a) (StmtTree a)
  | StmtTreeApplicative [StmtTree a]

instance Outputable a => Outputable (StmtTree a) where
  ppr :: StmtTree a -> MsgDoc
ppr (StmtTreeOne a
x)          = MsgDoc -> MsgDoc
parens (String -> MsgDoc
text String
"StmtTreeOne" MsgDoc -> MsgDoc -> MsgDoc
<+> a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr a
x)
  ppr (StmtTreeBind StmtTree a
x StmtTree a
y)       = MsgDoc -> MsgDoc
parens (MsgDoc -> Int -> MsgDoc -> MsgDoc
hang (String -> MsgDoc
text String
"StmtTreeBind")
                                            Int
2 ([MsgDoc] -> MsgDoc
sep [StmtTree a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr StmtTree a
x, StmtTree a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr StmtTree a
y]))
  ppr (StmtTreeApplicative [StmtTree a]
xs) = MsgDoc -> MsgDoc
parens (MsgDoc -> Int -> MsgDoc -> MsgDoc
hang (String -> MsgDoc
text String
"StmtTreeApplicative")
                                            Int
2 ([MsgDoc] -> MsgDoc
vcat ((StmtTree a -> MsgDoc) -> [StmtTree a] -> [MsgDoc]
forall a b. (a -> b) -> [a] -> [b]
map StmtTree a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr [StmtTree a]
xs)))

flattenStmtTree :: StmtTree a -> [a]
flattenStmtTree :: forall a. StmtTree a -> [a]
flattenStmtTree StmtTree a
t = StmtTree a -> [a] -> [a]
forall {a}. StmtTree a -> [a] -> [a]
go StmtTree a
t []
 where
  go :: StmtTree a -> [a] -> [a]
go (StmtTreeOne a
a) [a]
as = a
a a -> [a] -> [a]
forall a. a -> [a] -> [a]
: [a]
as
  go (StmtTreeBind StmtTree a
l StmtTree a
r) [a]
as = StmtTree a -> [a] -> [a]
go StmtTree a
l (StmtTree a -> [a] -> [a]
go StmtTree a
r [a]
as)
  go (StmtTreeApplicative [StmtTree a]
ts) [a]
as = (StmtTree a -> [a] -> [a]) -> [a] -> [StmtTree a] -> [a]
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr StmtTree a -> [a] -> [a]
go [a]
as [StmtTree a]
ts

type ExprStmtTree = StmtTree (ExprLStmt GhcRn, FreeVars)
type Cost = Int

-- | Turn a sequence of statements into an ExprStmtTree using a
-- heuristic algorithm.  /O(n^2)/
mkStmtTreeHeuristic :: [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeHeuristic :: [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeHeuristic [(ExprLStmt GhcRn, FreeVars)
one] = (ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (ExprLStmt GhcRn, FreeVars)
one
mkStmtTreeHeuristic [(ExprLStmt GhcRn, FreeVars)]
stmts =
  case [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
segments [(ExprLStmt GhcRn, FreeVars)]
stmts of
    [[(ExprLStmt GhcRn, FreeVars)]
one] -> [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
split [(ExprLStmt GhcRn, FreeVars)]
one
    [[(ExprLStmt GhcRn, FreeVars)]]
segs -> [ExprStmtTree] -> ExprStmtTree
forall a. [StmtTree a] -> StmtTree a
StmtTreeApplicative (([(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree)
-> [[(ExprLStmt GhcRn, FreeVars)]] -> [ExprStmtTree]
forall a b. (a -> b) -> [a] -> [b]
map [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
split [[(ExprLStmt GhcRn, FreeVars)]]
segs)
 where
  split :: [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
split [(ExprLStmt GhcRn, FreeVars)
one] = (ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (ExprLStmt GhcRn, FreeVars)
one
  split [(ExprLStmt GhcRn, FreeVars)]
stmts =
    ExprStmtTree -> ExprStmtTree -> ExprStmtTree
forall a. StmtTree a -> StmtTree a -> StmtTree a
StmtTreeBind ([(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeHeuristic [(ExprLStmt GhcRn, FreeVars)]
before) ([(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeHeuristic [(ExprLStmt GhcRn, FreeVars)]
after)
    where ([(ExprLStmt GhcRn, FreeVars)]
before, [(ExprLStmt GhcRn, FreeVars)]
after) = [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)])
splitSegment [(ExprLStmt GhcRn, FreeVars)]
stmts

-- | Turn a sequence of statements into an ExprStmtTree optimally,
-- using dynamic programming.  /O(n^3)/
mkStmtTreeOptimal :: [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeOptimal :: [(ExprLStmt GhcRn, FreeVars)] -> ExprStmtTree
mkStmtTreeOptimal [(ExprLStmt GhcRn, FreeVars)]
stmts =
  ASSERT(not (null stmts)) -- the empty case is handled by the caller;
                           -- we don't support empty StmtTrees.
  (ExprStmtTree, Int) -> ExprStmtTree
forall a b. (a, b) -> a
fst (Array (Int, Int) (ExprStmtTree, Int)
arr Array (Int, Int) (ExprStmtTree, Int)
-> (Int, Int) -> (ExprStmtTree, Int)
forall i e. Ix i => Array i e -> i -> e
! (Int
0,Int
n))
  where
    n :: Int
n = [(ExprLStmt GhcRn, FreeVars)] -> Int
forall (t :: * -> *) a. Foldable t => t a -> Int
length [(ExprLStmt GhcRn, FreeVars)]
stmts Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
1
    stmt_arr :: Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr = (Int, Int)
-> [(ExprLStmt GhcRn, FreeVars)]
-> Array Int (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => (i, i) -> [e] -> Array i e
listArray (Int
0,Int
n) [(ExprLStmt GhcRn, FreeVars)]
stmts

    -- lazy cache of optimal trees for subsequences of the input
    arr :: Array (Int,Int) (ExprStmtTree, Cost)
    arr :: Array (Int, Int) (ExprStmtTree, Int)
arr = ((Int, Int), (Int, Int))
-> [((Int, Int), (ExprStmtTree, Int))]
-> Array (Int, Int) (ExprStmtTree, Int)
forall i e. Ix i => (i, i) -> [(i, e)] -> Array i e
array ((Int
0,Int
0),(Int
n,Int
n))
             [ ((Int
lo,Int
hi), Int -> Int -> (ExprStmtTree, Int)
tree Int
lo Int
hi)
             | Int
lo <- [Int
0..Int
n]
             , Int
hi <- [Int
lo..Int
n] ]

    -- compute the optimal tree for the sequence [lo..hi]
    tree :: Int -> Int -> (ExprStmtTree, Int)
tree Int
lo Int
hi
      | Int
hi Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== Int
lo = ((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
lo), Int
1)
      | Bool
otherwise =
         case [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
segments [ Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
i | Int
i <- [Int
lo..Int
hi] ] of
           [] -> String -> (ExprStmtTree, Int)
forall a. String -> a
panic String
"mkStmtTree"
           [[(ExprLStmt GhcRn, FreeVars)]
_one] -> Int -> Int -> (ExprStmtTree, Int)
split Int
lo Int
hi
           [[(ExprLStmt GhcRn, FreeVars)]]
segs -> ([ExprStmtTree] -> ExprStmtTree
forall a. [StmtTree a] -> StmtTree a
StmtTreeApplicative [ExprStmtTree]
trees, [Int] -> Int
forall (t :: * -> *) a. (Foldable t, Ord a) => t a -> a
maximum [Int]
costs)
             where
               bounds :: [(Int, Int)]
bounds = ((Int, Int) -> [(ExprLStmt GhcRn, FreeVars)] -> (Int, Int))
-> (Int, Int) -> [[(ExprLStmt GhcRn, FreeVars)]] -> [(Int, Int)]
forall b a. (b -> a -> b) -> b -> [a] -> [b]
scanl (\(Int
_,Int
hi) [(ExprLStmt GhcRn, FreeVars)]
a -> (Int
hiInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1, Int
hi Int -> Int -> Int
forall a. Num a => a -> a -> a
+ [(ExprLStmt GhcRn, FreeVars)] -> Int
forall (t :: * -> *) a. Foldable t => t a -> Int
length [(ExprLStmt GhcRn, FreeVars)]
a)) (Int
0,Int
loInt -> Int -> Int
forall a. Num a => a -> a -> a
-Int
1) [[(ExprLStmt GhcRn, FreeVars)]]
segs
               ([ExprStmtTree]
trees,[Int]
costs) = [(ExprStmtTree, Int)] -> ([ExprStmtTree], [Int])
forall a b. [(a, b)] -> ([a], [b])
unzip (((Int, Int) -> (ExprStmtTree, Int))
-> [(Int, Int)] -> [(ExprStmtTree, Int)]
forall a b. (a -> b) -> [a] -> [b]
map ((Int -> Int -> (ExprStmtTree, Int))
-> (Int, Int) -> (ExprStmtTree, Int)
forall a b c. (a -> b -> c) -> (a, b) -> c
uncurry Int -> Int -> (ExprStmtTree, Int)
split) ([(Int, Int)] -> [(Int, Int)]
forall a. [a] -> [a]
tail [(Int, Int)]
bounds))

    -- find the best place to split the segment [lo..hi]
    split :: Int -> Int -> (ExprStmtTree, Cost)
    split :: Int -> Int -> (ExprStmtTree, Int)
split Int
lo Int
hi
      | Int
hi Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== Int
lo = ((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
lo), Int
1)
      | Bool
otherwise = (ExprStmtTree -> ExprStmtTree -> ExprStmtTree
forall a. StmtTree a -> StmtTree a -> StmtTree a
StmtTreeBind ExprStmtTree
before ExprStmtTree
after, Int
c1Int -> Int -> Int
forall a. Num a => a -> a -> a
+Int
c2)
        where
         -- As per the paper, for a sequence s1...sn, we want to find
         -- the split with the minimum cost, where the cost is the
         -- sum of the cost of the left and right subsequences.
         --
         -- As an optimisation (also in the paper) if the cost of
         -- s1..s(n-1) is different from the cost of s2..sn, we know
         -- that the optimal solution is the lower of the two.  Only
         -- in the case that these two have the same cost do we need
         -- to do the exhaustive search.
         --
         ((ExprStmtTree
before,Int
c1),(ExprStmtTree
after,Int
c2))
           | Int
hi Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
lo Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== Int
1
           = (((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
lo), Int
1),
              ((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
hi), Int
1))
           | Int
left_cost Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
< Int
right_cost
           = ((ExprStmtTree
left,Int
left_cost), ((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
hi), Int
1))
           | Int
left_cost Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> Int
right_cost
           = (((ExprLStmt GhcRn, FreeVars) -> ExprStmtTree
forall a. a -> StmtTree a
StmtTreeOne (Array Int (ExprLStmt GhcRn, FreeVars)
stmt_arr Array Int (ExprLStmt GhcRn, FreeVars)
-> Int -> (ExprLStmt GhcRn, FreeVars)
forall i e. Ix i => Array i e -> i -> e
! Int
lo), Int
1), (ExprStmtTree
right,Int
right_cost))
           | Bool
otherwise = (((ExprStmtTree, Int), (ExprStmtTree, Int))
 -> ((ExprStmtTree, Int), (ExprStmtTree, Int)) -> Ordering)
-> [((ExprStmtTree, Int), (ExprStmtTree, Int))]
-> ((ExprStmtTree, Int), (ExprStmtTree, Int))
forall (t :: * -> *) a.
Foldable t =>
(a -> a -> Ordering) -> t a -> a
minimumBy ((((ExprStmtTree, Int), (ExprStmtTree, Int)) -> Int)
-> ((ExprStmtTree, Int), (ExprStmtTree, Int))
-> ((ExprStmtTree, Int), (ExprStmtTree, Int))
-> Ordering
forall a b. Ord a => (b -> a) -> b -> b -> Ordering
comparing ((ExprStmtTree, Int), (ExprStmtTree, Int)) -> Int
forall {a} {a} {a}. Num a => ((a, a), (a, a)) -> a
cost) [((ExprStmtTree, Int), (ExprStmtTree, Int))]
alternatives
           where
             (ExprStmtTree
left, Int
left_cost) = Array (Int, Int) (ExprStmtTree, Int)
arr Array (Int, Int) (ExprStmtTree, Int)
-> (Int, Int) -> (ExprStmtTree, Int)
forall i e. Ix i => Array i e -> i -> e
! (Int
lo,Int
hiInt -> Int -> Int
forall a. Num a => a -> a -> a
-Int
1)
             (ExprStmtTree
right, Int
right_cost) = Array (Int, Int) (ExprStmtTree, Int)
arr Array (Int, Int) (ExprStmtTree, Int)
-> (Int, Int) -> (ExprStmtTree, Int)
forall i e. Ix i => Array i e -> i -> e
! (Int
loInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1,Int
hi)
             cost :: ((a, a), (a, a)) -> a
cost ((a
_,a
c1),(a
_,a
c2)) = a
c1 a -> a -> a
forall a. Num a => a -> a -> a
+ a
c2
             alternatives :: [((ExprStmtTree, Int), (ExprStmtTree, Int))]
alternatives = [ (Array (Int, Int) (ExprStmtTree, Int)
arr Array (Int, Int) (ExprStmtTree, Int)
-> (Int, Int) -> (ExprStmtTree, Int)
forall i e. Ix i => Array i e -> i -> e
! (Int
lo,Int
k), Array (Int, Int) (ExprStmtTree, Int)
arr Array (Int, Int) (ExprStmtTree, Int)
-> (Int, Int) -> (ExprStmtTree, Int)
forall i e. Ix i => Array i e -> i -> e
! (Int
kInt -> Int -> Int
forall a. Num a => a -> a -> a
+Int
1,Int
hi))
                            | Int
k <- [Int
lo .. Int
hiInt -> Int -> Int
forall a. Num a => a -> a -> a
-Int
1] ]


-- | Turn the ExprStmtTree back into a sequence of statements, using
-- ApplicativeStmt where necessary.
stmtTreeToStmts
  :: MonadNames
  -> HsStmtContext GhcRn
  -> ExprStmtTree
  -> [ExprLStmt GhcRn]             -- ^ the "tail"
  -> FreeVars                     -- ^ free variables of the tail
  -> RnM ( [ExprLStmt GhcRn]       -- ( output statements,
         , FreeVars )             -- , things we needed

-- If we have a single bind, and we can do it without a join, transform
-- to an ApplicativeStmt.  This corresponds to the rule
--   dsBlock [pat <- rhs] (return expr) = expr <$> rhs
-- In the spec, but we do it here rather than in the desugarer,
-- because we need the typechecker to typecheck the <$> form rather than
-- the bind form, which would give rise to a Monad constraint.
stmtTreeToStmts :: MonadNames
-> HsStmtContext GhcRn
-> ExprStmtTree
-> [ExprLStmt GhcRn]
-> FreeVars
-> RnM ([ExprLStmt GhcRn], FreeVars)
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt (StmtTreeOne (L SrcSpan
_ (BindStmt XBindStmt GhcRn GhcRn (LHsExpr GhcRn)
xbs LPat GhcRn
pat LHsExpr GhcRn
rhs), FreeVars
_))
                [ExprLStmt GhcRn]
tail FreeVars
_tail_fvs
  | Bool -> Bool
not (LPat GhcRn -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat GhcRn
pat), (Bool
False,[ExprLStmt GhcRn]
tail') <- MonadNames -> [ExprLStmt GhcRn] -> (Bool, [ExprLStmt GhcRn])
needJoin MonadNames
monad_names [ExprLStmt GhcRn]
tail
  -- See Note [ApplicativeDo and strict patterns]
  = HsStmtContext GhcRn
-> [ApplicativeArg GhcRn]
-> Bool
-> [ExprLStmt GhcRn]
-> RnM ([ExprLStmt GhcRn], FreeVars)
mkApplicativeStmt HsStmtContext GhcRn
ctxt [ApplicativeArgOne :: forall idL.
XApplicativeArgOne idL
-> LPat idL -> LHsExpr idL -> Bool -> ApplicativeArg idL
ApplicativeArgOne
                            { xarg_app_arg_one :: XApplicativeArgOne GhcRn
xarg_app_arg_one = XBindStmtRn -> Maybe (SyntaxExpr GhcRn)
xbsrn_failOp XBindStmt GhcRn GhcRn (LHsExpr GhcRn)
XBindStmtRn
xbs
                            , app_arg_pattern :: LPat GhcRn
app_arg_pattern  = LPat GhcRn
pat
                            , arg_expr :: LHsExpr GhcRn
arg_expr         = LHsExpr GhcRn
rhs
                            , is_body_stmt :: Bool
is_body_stmt     = Bool
False
                            }]
                      Bool
False [ExprLStmt GhcRn]
tail'
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt (StmtTreeOne (L SrcSpan
_ (BodyStmt XBodyStmt GhcRn GhcRn (LHsExpr GhcRn)
_ LHsExpr GhcRn
rhs SyntaxExpr GhcRn
_ SyntaxExpr GhcRn
_),FreeVars
_))
                [ExprLStmt GhcRn]
tail FreeVars
_tail_fvs
  | (Bool
False,[ExprLStmt GhcRn]
tail') <- MonadNames -> [ExprLStmt GhcRn] -> (Bool, [ExprLStmt GhcRn])
needJoin MonadNames
monad_names [ExprLStmt GhcRn]
tail
  = HsStmtContext GhcRn
-> [ApplicativeArg GhcRn]
-> Bool
-> [ExprLStmt GhcRn]
-> RnM ([ExprLStmt GhcRn], FreeVars)
mkApplicativeStmt HsStmtContext GhcRn
ctxt
      [ApplicativeArgOne :: forall idL.
XApplicativeArgOne idL
-> LPat idL -> LHsExpr idL -> Bool -> ApplicativeArg idL
ApplicativeArgOne
       { xarg_app_arg_one :: XApplicativeArgOne GhcRn
xarg_app_arg_one = XApplicativeArgOne GhcRn
forall a. Maybe a
Nothing
       , app_arg_pattern :: LPat GhcRn
app_arg_pattern  = LPat GhcRn
nlWildPatName
       , arg_expr :: LHsExpr GhcRn
arg_expr         = LHsExpr GhcRn
rhs
       , is_body_stmt :: Bool
is_body_stmt     = Bool
True
       }] Bool
False [ExprLStmt GhcRn]
tail'

stmtTreeToStmts MonadNames
_monad_names HsStmtContext GhcRn
_ctxt (StmtTreeOne (ExprLStmt GhcRn
s,FreeVars
_)) [ExprLStmt GhcRn]
tail FreeVars
_tail_fvs =
  ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (ExprLStmt GhcRn
s ExprLStmt GhcRn -> [ExprLStmt GhcRn] -> [ExprLStmt GhcRn]
forall a. a -> [a] -> [a]
: [ExprLStmt GhcRn]
tail, FreeVars
emptyNameSet)

stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt (StmtTreeBind ExprStmtTree
before ExprStmtTree
after) [ExprLStmt GhcRn]
tail FreeVars
tail_fvs = do
  ([ExprLStmt GhcRn]
stmts1, FreeVars
fvs1) <- MonadNames
-> HsStmtContext GhcRn
-> ExprStmtTree
-> [ExprLStmt GhcRn]
-> FreeVars
-> RnM ([ExprLStmt GhcRn], FreeVars)
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt ExprStmtTree
after [ExprLStmt GhcRn]
tail FreeVars
tail_fvs
  let tail1_fvs :: FreeVars
tail1_fvs = [FreeVars] -> FreeVars
unionNameSets (FreeVars
tail_fvs FreeVars -> [FreeVars] -> [FreeVars]
forall a. a -> [a] -> [a]
: ((ExprLStmt GhcRn, FreeVars) -> FreeVars)
-> [(ExprLStmt GhcRn, FreeVars)] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map (ExprLStmt GhcRn, FreeVars) -> FreeVars
forall a b. (a, b) -> b
snd (ExprStmtTree -> [(ExprLStmt GhcRn, FreeVars)]
forall a. StmtTree a -> [a]
flattenStmtTree ExprStmtTree
after))
  ([ExprLStmt GhcRn]
stmts2, FreeVars
fvs2) <- MonadNames
-> HsStmtContext GhcRn
-> ExprStmtTree
-> [ExprLStmt GhcRn]
-> FreeVars
-> RnM ([ExprLStmt GhcRn], FreeVars)
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt ExprStmtTree
before [ExprLStmt GhcRn]
stmts1 FreeVars
tail1_fvs
  ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([ExprLStmt GhcRn]
stmts2, FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2)

stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt (StmtTreeApplicative [ExprStmtTree]
trees) [ExprLStmt GhcRn]
tail FreeVars
tail_fvs = do
   [(ApplicativeArg GhcRn, FreeVars)]
pairs <- (ExprStmtTree
 -> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars))
-> [ExprStmtTree]
-> IOEnv (Env TcGblEnv TcLclEnv) [(ApplicativeArg GhcRn, FreeVars)]
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM (HsStmtContext GhcRn
-> FreeVars
-> ExprStmtTree
-> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars)
stmtTreeArg HsStmtContext GhcRn
ctxt FreeVars
tail_fvs) [ExprStmtTree]
trees
   DynFlags
dflags <- IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
   let ([ApplicativeArg GhcRn]
stmts', [FreeVars]
fvss) = [(ApplicativeArg GhcRn, FreeVars)]
-> ([ApplicativeArg GhcRn], [FreeVars])
forall a b. [(a, b)] -> ([a], [b])
unzip [(ApplicativeArg GhcRn, FreeVars)]
pairs
   let (Bool
need_join, [ExprLStmt GhcRn]
tail') =
     -- See Note [ApplicativeDo and refutable patterns]
         if (ApplicativeArg GhcRn -> Bool) -> [ApplicativeArg GhcRn] -> Bool
forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
any (DynFlags -> ApplicativeArg GhcRn -> Bool
hasRefutablePattern DynFlags
dflags) [ApplicativeArg GhcRn]
stmts'
         then (Bool
True, [ExprLStmt GhcRn]
tail)
         else MonadNames -> [ExprLStmt GhcRn] -> (Bool, [ExprLStmt GhcRn])
needJoin MonadNames
monad_names [ExprLStmt GhcRn]
tail

   ([ExprLStmt GhcRn]
stmts, FreeVars
fvs) <- HsStmtContext GhcRn
-> [ApplicativeArg GhcRn]
-> Bool
-> [ExprLStmt GhcRn]
-> RnM ([ExprLStmt GhcRn], FreeVars)
mkApplicativeStmt HsStmtContext GhcRn
ctxt [ApplicativeArg GhcRn]
stmts' Bool
need_join [ExprLStmt GhcRn]
tail'
   ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ([ExprLStmt GhcRn]
stmts, [FreeVars] -> FreeVars
unionNameSets (FreeVars
fvsFreeVars -> [FreeVars] -> [FreeVars]
forall a. a -> [a] -> [a]
:[FreeVars]
fvss))
 where
   stmtTreeArg :: HsStmtContext GhcRn
-> FreeVars
-> ExprStmtTree
-> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars)
stmtTreeArg HsStmtContext GhcRn
_ctxt FreeVars
_tail_fvs (StmtTreeOne (L SrcSpan
_ (BindStmt XBindStmt GhcRn GhcRn (LHsExpr GhcRn)
xbs LPat GhcRn
pat LHsExpr GhcRn
exp), FreeVars
_))
     = (ApplicativeArg GhcRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (ApplicativeArgOne :: forall idL.
XApplicativeArgOne idL
-> LPat idL -> LHsExpr idL -> Bool -> ApplicativeArg idL
ApplicativeArgOne
               { xarg_app_arg_one :: XApplicativeArgOne GhcRn
xarg_app_arg_one = XBindStmtRn -> Maybe (SyntaxExpr GhcRn)
xbsrn_failOp XBindStmt GhcRn GhcRn (LHsExpr GhcRn)
XBindStmtRn
xbs
               , app_arg_pattern :: LPat GhcRn
app_arg_pattern  = LPat GhcRn
pat
               , arg_expr :: LHsExpr GhcRn
arg_expr         = LHsExpr GhcRn
exp
               , is_body_stmt :: Bool
is_body_stmt     = Bool
False
               }, FreeVars
emptyFVs)
   stmtTreeArg HsStmtContext GhcRn
_ctxt FreeVars
_tail_fvs (StmtTreeOne (L SrcSpan
_ (BodyStmt XBodyStmt GhcRn GhcRn (LHsExpr GhcRn)
_ LHsExpr GhcRn
exp SyntaxExpr GhcRn
_ SyntaxExpr GhcRn
_), FreeVars
_)) =
     (ApplicativeArg GhcRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (ApplicativeArgOne :: forall idL.
XApplicativeArgOne idL
-> LPat idL -> LHsExpr idL -> Bool -> ApplicativeArg idL
ApplicativeArgOne
             { xarg_app_arg_one :: XApplicativeArgOne GhcRn
xarg_app_arg_one = XApplicativeArgOne GhcRn
forall a. Maybe a
Nothing
             , app_arg_pattern :: LPat GhcRn
app_arg_pattern  = LPat GhcRn
nlWildPatName
             , arg_expr :: LHsExpr GhcRn
arg_expr         = LHsExpr GhcRn
exp
             , is_body_stmt :: Bool
is_body_stmt     = Bool
True
             }, FreeVars
emptyFVs)
   stmtTreeArg HsStmtContext GhcRn
ctxt FreeVars
tail_fvs ExprStmtTree
tree = do
     let stmts :: [(ExprLStmt GhcRn, FreeVars)]
stmts = ExprStmtTree -> [(ExprLStmt GhcRn, FreeVars)]
forall a. StmtTree a -> [a]
flattenStmtTree ExprStmtTree
tree
         pvarset :: FreeVars
pvarset = [Name] -> FreeVars
mkNameSet (((ExprLStmt GhcRn, FreeVars) -> [Name])
-> [(ExprLStmt GhcRn, FreeVars)] -> [Name]
forall (t :: * -> *) a b. Foldable t => (a -> [b]) -> t a -> [b]
concatMap (StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> [Name]
forall (idL :: Pass) (idR :: Pass) body.
CollectPass (GhcPass idL) =>
StmtLR (GhcPass idL) (GhcPass idR) body -> [IdP (GhcPass idL)]
collectStmtBinders(StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> [Name])
-> ((ExprLStmt GhcRn, FreeVars)
    -> StmtLR GhcRn GhcRn (LHsExpr GhcRn))
-> (ExprLStmt GhcRn, FreeVars)
-> [Name]
forall b c a. (b -> c) -> (a -> b) -> a -> c
.ExprLStmt GhcRn -> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall l e. GenLocated l e -> e
unLoc(ExprLStmt GhcRn -> StmtLR GhcRn GhcRn (LHsExpr GhcRn))
-> ((ExprLStmt GhcRn, FreeVars) -> ExprLStmt GhcRn)
-> (ExprLStmt GhcRn, FreeVars)
-> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall b c a. (b -> c) -> (a -> b) -> a -> c
.(ExprLStmt GhcRn, FreeVars) -> ExprLStmt GhcRn
forall a b. (a, b) -> a
fst) [(ExprLStmt GhcRn, FreeVars)]
stmts)
                     FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
tail_fvs
         pvars :: [Name]
pvars = FreeVars -> [Name]
nameSetElemsStable FreeVars
pvarset
           -- See Note [Deterministic ApplicativeDo and RecursiveDo desugaring]
         pat :: LPat GhcRn
pat = [IdP GhcRn] -> LPat GhcRn
mkBigLHsVarPatTup [Name]
[IdP GhcRn]
pvars
         tup :: LHsExpr GhcRn
tup = [IdP GhcRn] -> LHsExpr GhcRn
forall (id :: Pass). [IdP (GhcPass id)] -> LHsExpr (GhcPass id)
mkBigLHsVarTup [Name]
[IdP GhcRn]
pvars
     ([ExprLStmt GhcRn]
stmts',FreeVars
fvs2) <- MonadNames
-> HsStmtContext GhcRn
-> ExprStmtTree
-> [ExprLStmt GhcRn]
-> FreeVars
-> RnM ([ExprLStmt GhcRn], FreeVars)
stmtTreeToStmts MonadNames
monad_names HsStmtContext GhcRn
ctxt ExprStmtTree
tree [] FreeVars
pvarset
     (HsExpr GhcRn
mb_ret, FreeVars
fvs1) <-
        if | L SrcSpan
_ ApplicativeStmt{} <- [ExprLStmt GhcRn] -> ExprLStmt GhcRn
forall a. [a] -> a
last [ExprLStmt GhcRn]
stmts' ->
             (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsExpr GhcRn -> HsExpr GhcRn
forall l e. GenLocated l e -> e
unLoc LHsExpr GhcRn
tup, FreeVars
emptyNameSet)
           | Bool
otherwise -> do
             (HsExpr GhcRn
ret, FreeVars
_) <- HsStmtContext GhcRn -> Name -> TcM (HsExpr GhcRn, FreeVars)
forall p. HsStmtContext p -> Name -> TcM (HsExpr GhcRn, FreeVars)
lookupQualifiedDoExpr HsStmtContext GhcRn
ctxt Name
returnMName
             let expr :: HsExpr GhcRn
expr = XApp GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XApp p -> LHsExpr p -> LHsExpr p -> HsExpr p
HsApp NoExtField
XApp GhcRn
noExtField (HsExpr GhcRn -> LHsExpr GhcRn
forall e. e -> Located e
noLoc HsExpr GhcRn
ret) LHsExpr GhcRn
tup
             (HsExpr GhcRn, FreeVars) -> TcM (HsExpr GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (HsExpr GhcRn
expr, FreeVars
emptyFVs)
     (ApplicativeArg GhcRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (ApplicativeArg GhcRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( ApplicativeArgMany :: forall idL.
XApplicativeArgMany idL
-> [ExprLStmt idL]
-> HsExpr idL
-> LPat idL
-> HsStmtContext GhcRn
-> ApplicativeArg idL
ApplicativeArgMany
              { xarg_app_arg_many :: XApplicativeArgMany GhcRn
xarg_app_arg_many = NoExtField
XApplicativeArgMany GhcRn
noExtField
              , app_stmts :: [ExprLStmt GhcRn]
app_stmts         = [ExprLStmt GhcRn]
stmts'
              , final_expr :: HsExpr GhcRn
final_expr        = HsExpr GhcRn
mb_ret
              , bv_pattern :: LPat GhcRn
bv_pattern        = LPat GhcRn
pat
              , stmt_context :: HsStmtContext GhcRn
stmt_context      = HsStmtContext GhcRn
ctxt
              }
            , FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2)


-- | Divide a sequence of statements into segments, where no segment
-- depends on any variables defined by a statement in another segment.
segments
  :: [(ExprLStmt GhcRn, FreeVars)]
  -> [[(ExprLStmt GhcRn, FreeVars)]]
segments :: [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
segments [(ExprLStmt GhcRn, FreeVars)]
stmts = (([(ExprLStmt GhcRn, FreeVars)], Bool)
 -> [(ExprLStmt GhcRn, FreeVars)])
-> [([(ExprLStmt GhcRn, FreeVars)], Bool)]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a b. (a -> b) -> [a] -> [b]
map ([(ExprLStmt GhcRn, FreeVars)], Bool)
-> [(ExprLStmt GhcRn, FreeVars)]
forall a b. (a, b) -> a
fst ([([(ExprLStmt GhcRn, FreeVars)], Bool)]
 -> [[(ExprLStmt GhcRn, FreeVars)]])
-> [([(ExprLStmt GhcRn, FreeVars)], Bool)]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a b. (a -> b) -> a -> b
$ [[(ExprLStmt GhcRn, FreeVars)]]
-> [([(ExprLStmt GhcRn, FreeVars)], Bool)]
forall {a} {b} {b}.
[[(LStmt a b, b)]] -> [([(LStmt a b, b)], Bool)]
merge ([[(ExprLStmt GhcRn, FreeVars)]]
 -> [([(ExprLStmt GhcRn, FreeVars)], Bool)])
-> [[(ExprLStmt GhcRn, FreeVars)]]
-> [([(ExprLStmt GhcRn, FreeVars)], Bool)]
forall a b. (a -> b) -> a -> b
$ [[(ExprLStmt GhcRn, FreeVars)]] -> [[(ExprLStmt GhcRn, FreeVars)]]
forall a. [a] -> [a]
reverse ([[(ExprLStmt GhcRn, FreeVars)]]
 -> [[(ExprLStmt GhcRn, FreeVars)]])
-> [[(ExprLStmt GhcRn, FreeVars)]]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a b. (a -> b) -> a -> b
$ ([(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)])
-> [[(ExprLStmt GhcRn, FreeVars)]]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a b. (a -> b) -> [a] -> [b]
map [(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. [a] -> [a]
reverse ([[(ExprLStmt GhcRn, FreeVars)]]
 -> [[(ExprLStmt GhcRn, FreeVars)]])
-> [[(ExprLStmt GhcRn, FreeVars)]]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a b. (a -> b) -> a -> b
$ [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
walk ([(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. [a] -> [a]
reverse [(ExprLStmt GhcRn, FreeVars)]
stmts)
  where
    allvars :: FreeVars
allvars = [Name] -> FreeVars
mkNameSet (((ExprLStmt GhcRn, FreeVars) -> [Name])
-> [(ExprLStmt GhcRn, FreeVars)] -> [Name]
forall (t :: * -> *) a b. Foldable t => (a -> [b]) -> t a -> [b]
concatMap (StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> [Name]
forall (idL :: Pass) (idR :: Pass) body.
CollectPass (GhcPass idL) =>
StmtLR (GhcPass idL) (GhcPass idR) body -> [IdP (GhcPass idL)]
collectStmtBinders(StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> [Name])
-> ((ExprLStmt GhcRn, FreeVars)
    -> StmtLR GhcRn GhcRn (LHsExpr GhcRn))
-> (ExprLStmt GhcRn, FreeVars)
-> [Name]
forall b c a. (b -> c) -> (a -> b) -> a -> c
.ExprLStmt GhcRn -> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall l e. GenLocated l e -> e
unLoc(ExprLStmt GhcRn -> StmtLR GhcRn GhcRn (LHsExpr GhcRn))
-> ((ExprLStmt GhcRn, FreeVars) -> ExprLStmt GhcRn)
-> (ExprLStmt GhcRn, FreeVars)
-> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall b c a. (b -> c) -> (a -> b) -> a -> c
.(ExprLStmt GhcRn, FreeVars) -> ExprLStmt GhcRn
forall a b. (a, b) -> a
fst) [(ExprLStmt GhcRn, FreeVars)]
stmts)

    -- We would rather not have a segment that just has LetStmts in
    -- it, so combine those with an adjacent segment where possible.
    merge :: [[(LStmt a b, b)]] -> [([(LStmt a b, b)], Bool)]
merge [] = []
    merge ([(LStmt a b, b)]
seg : [[(LStmt a b, b)]]
segs)
       = case [([(LStmt a b, b)], Bool)]
rest of
          [] -> [([(LStmt a b, b)]
seg,Bool
all_lets)]
          (([(LStmt a b, b)]
s,Bool
s_lets):[([(LStmt a b, b)], Bool)]
ss) | Bool
all_lets Bool -> Bool -> Bool
|| Bool
s_lets
               -> ([(LStmt a b, b)]
seg [(LStmt a b, b)] -> [(LStmt a b, b)] -> [(LStmt a b, b)]
forall a. [a] -> [a] -> [a]
++ [(LStmt a b, b)]
s, Bool
all_lets Bool -> Bool -> Bool
&& Bool
s_lets) ([(LStmt a b, b)], Bool)
-> [([(LStmt a b, b)], Bool)] -> [([(LStmt a b, b)], Bool)]
forall a. a -> [a] -> [a]
: [([(LStmt a b, b)], Bool)]
ss
          [([(LStmt a b, b)], Bool)]
_otherwise -> ([(LStmt a b, b)]
seg,Bool
all_lets) ([(LStmt a b, b)], Bool)
-> [([(LStmt a b, b)], Bool)] -> [([(LStmt a b, b)], Bool)]
forall a. a -> [a] -> [a]
: [([(LStmt a b, b)], Bool)]
rest
      where
        rest :: [([(LStmt a b, b)], Bool)]
rest = [[(LStmt a b, b)]] -> [([(LStmt a b, b)], Bool)]
merge [[(LStmt a b, b)]]
segs
        all_lets :: Bool
all_lets = ((LStmt a b, b) -> Bool) -> [(LStmt a b, b)] -> Bool
forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
all (LStmt a b -> Bool
forall a b. LStmt a b -> Bool
isLetStmt (LStmt a b -> Bool)
-> ((LStmt a b, b) -> LStmt a b) -> (LStmt a b, b) -> Bool
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (LStmt a b, b) -> LStmt a b
forall a b. (a, b) -> a
fst) [(LStmt a b, b)]
seg

    -- walk splits the statement sequence into segments, traversing
    -- the sequence from the back to the front, and keeping track of
    -- the set of free variables of the current segment.  Whenever
    -- this set of free variables is empty, we have a complete segment.
    walk :: [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
    walk :: [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
walk [] = []
    walk ((ExprLStmt GhcRn
stmt,FreeVars
fvs) : [(ExprLStmt GhcRn, FreeVars)]
stmts) = ((ExprLStmt GhcRn
stmt,FreeVars
fvs) (ExprLStmt GhcRn, FreeVars)
-> [(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. a -> [a] -> [a]
: [(ExprLStmt GhcRn, FreeVars)]
seg) [(ExprLStmt GhcRn, FreeVars)]
-> [[(ExprLStmt GhcRn, FreeVars)]]
-> [[(ExprLStmt GhcRn, FreeVars)]]
forall a. a -> [a] -> [a]
: [(ExprLStmt GhcRn, FreeVars)] -> [[(ExprLStmt GhcRn, FreeVars)]]
walk [(ExprLStmt GhcRn, FreeVars)]
rest
      where ([(ExprLStmt GhcRn, FreeVars)]
seg,[(ExprLStmt GhcRn, FreeVars)]
rest) = FreeVars
-> [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)])
chunter FreeVars
fvs' [(ExprLStmt GhcRn, FreeVars)]
stmts
            (FreeVars
_, FreeVars
fvs') = ExprLStmt GhcRn -> FreeVars -> (FreeVars, FreeVars)
stmtRefs ExprLStmt GhcRn
stmt FreeVars
fvs

    chunter :: FreeVars
-> [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)])
chunter FreeVars
_ [] = ([], [])
    chunter FreeVars
vars ((ExprLStmt GhcRn
stmt,FreeVars
fvs) : [(ExprLStmt GhcRn, FreeVars)]
rest)
       | Bool -> Bool
not (FreeVars -> Bool
isEmptyNameSet FreeVars
vars)
       Bool -> Bool -> Bool
|| ExprLStmt GhcRn -> Bool
isStrictPatternBind ExprLStmt GhcRn
stmt
           -- See Note [ApplicativeDo and strict patterns]
       = ((ExprLStmt GhcRn
stmt,FreeVars
fvs) (ExprLStmt GhcRn, FreeVars)
-> [(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. a -> [a] -> [a]
: [(ExprLStmt GhcRn, FreeVars)]
chunk, [(ExprLStmt GhcRn, FreeVars)]
rest')
       where ([(ExprLStmt GhcRn, FreeVars)]
chunk,[(ExprLStmt GhcRn, FreeVars)]
rest') = FreeVars
-> [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)])
chunter FreeVars
vars' [(ExprLStmt GhcRn, FreeVars)]
rest
             (FreeVars
pvars, FreeVars
evars) = ExprLStmt GhcRn -> FreeVars -> (FreeVars, FreeVars)
stmtRefs ExprLStmt GhcRn
stmt FreeVars
fvs
             vars' :: FreeVars
vars' = (FreeVars
vars FreeVars -> FreeVars -> FreeVars
`minusNameSet` FreeVars
pvars) FreeVars -> FreeVars -> FreeVars
`unionNameSet` FreeVars
evars
    chunter FreeVars
_ [(ExprLStmt GhcRn, FreeVars)]
rest = ([], [(ExprLStmt GhcRn, FreeVars)]
rest)

    stmtRefs :: ExprLStmt GhcRn -> FreeVars -> (FreeVars, FreeVars)
stmtRefs ExprLStmt GhcRn
stmt FreeVars
fvs
      | ExprLStmt GhcRn -> Bool
forall a b. LStmt a b -> Bool
isLetStmt ExprLStmt GhcRn
stmt = (FreeVars
pvars, FreeVars
fvs' FreeVars -> FreeVars -> FreeVars
`minusNameSet` FreeVars
pvars)
      | Bool
otherwise      = (FreeVars
pvars, FreeVars
fvs')
      where fvs' :: FreeVars
fvs' = FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`intersectNameSet` FreeVars
allvars
            pvars :: FreeVars
pvars = [Name] -> FreeVars
mkNameSet (StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> [IdP GhcRn]
forall (idL :: Pass) (idR :: Pass) body.
CollectPass (GhcPass idL) =>
StmtLR (GhcPass idL) (GhcPass idR) body -> [IdP (GhcPass idL)]
collectStmtBinders (ExprLStmt GhcRn -> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall l e. GenLocated l e -> e
unLoc ExprLStmt GhcRn
stmt))

    isStrictPatternBind :: ExprLStmt GhcRn -> Bool
    isStrictPatternBind :: ExprLStmt GhcRn -> Bool
isStrictPatternBind (L SrcSpan
_ (BindStmt XBindStmt GhcRn GhcRn (LHsExpr GhcRn)
_ LPat GhcRn
pat LHsExpr GhcRn
_)) = LPat GhcRn -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat GhcRn
pat
    isStrictPatternBind ExprLStmt GhcRn
_ = Bool
False

{-
Note [ApplicativeDo and strict patterns]

A strict pattern match is really a dependency.  For example,

do
  (x,y) <- A
  z <- B
  return C

The pattern (_,_) must be matched strictly before we do B.  If we
allowed this to be transformed into

  (\(x,y) -> \z -> C) <$> A <*> B

then it could be lazier than the standard desuraging using >>=.  See #13875
for more examples.

Thus, whenever we have a strict pattern match, we treat it as a
dependency between that statement and the following one.  The
dependency prevents those two statements from being performed "in
parallel" in an ApplicativeStmt, but doesn't otherwise affect what we
can do with the rest of the statements in the same "do" expression.
-}

isStrictPattern :: LPat (GhcPass p) -> Bool
isStrictPattern :: forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
lpat =
  case GenLocated SrcSpan (Pat (GhcPass p)) -> Pat (GhcPass p)
forall l e. GenLocated l e -> e
unLoc GenLocated SrcSpan (Pat (GhcPass p))
LPat (GhcPass p)
lpat of
    WildPat{}       -> Bool
False
    VarPat{}        -> Bool
False
    LazyPat{}       -> Bool
False
    AsPat XAsPat (GhcPass p)
_ Located (IdP (GhcPass p))
_ LPat (GhcPass p)
p     -> LPat (GhcPass p) -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
p
    ParPat XParPat (GhcPass p)
_ LPat (GhcPass p)
p      -> LPat (GhcPass p) -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
p
    ViewPat XViewPat (GhcPass p)
_ LHsExpr (GhcPass p)
_ LPat (GhcPass p)
p   -> LPat (GhcPass p) -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
p
    SigPat XSigPat (GhcPass p)
_ LPat (GhcPass p)
p HsPatSigType (NoGhcTc (GhcPass p))
_    -> LPat (GhcPass p) -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
p
    BangPat{}       -> Bool
True
    ListPat{}       -> Bool
True
    TuplePat{}      -> Bool
True
    SumPat{}        -> Bool
True
    ConPat{}        -> Bool
True
    LitPat{}        -> Bool
True
    NPat{}          -> Bool
True
    NPlusKPat{}     -> Bool
True
    SplicePat{}     -> Bool
True
    XPat{}          -> String -> Bool
forall a. String -> a
panic String
"isStrictPattern: XPat"

{-
Note [ApplicativeDo and refutable patterns]

Refutable patterns in do blocks are desugared to use the monadic 'fail' operation.
This means that sometimes an applicative block needs to be wrapped in 'join' simply because
of a refutable pattern, in order for the types to work out.

-}

hasRefutablePattern :: DynFlags -> ApplicativeArg GhcRn -> Bool
hasRefutablePattern :: DynFlags -> ApplicativeArg GhcRn -> Bool
hasRefutablePattern DynFlags
dflags (ApplicativeArgOne { app_arg_pattern :: forall idL. ApplicativeArg idL -> LPat idL
app_arg_pattern = LPat GhcRn
pat
                                              , is_body_stmt :: forall idL. ApplicativeArg idL -> Bool
is_body_stmt = Bool
False}) =
                                         Bool -> Bool
not (DynFlags -> LPat GhcRn -> Bool
forall (p :: Pass).
OutputableBndrId p =>
DynFlags -> LPat (GhcPass p) -> Bool
isIrrefutableHsPat DynFlags
dflags LPat GhcRn
pat)
hasRefutablePattern DynFlags
_ ApplicativeArg GhcRn
_ = Bool
False

isLetStmt :: LStmt a b -> Bool
isLetStmt :: forall a b. LStmt a b -> Bool
isLetStmt (L SrcSpan
_ LetStmt{}) = Bool
True
isLetStmt GenLocated SrcSpan (StmtLR a a b)
_ = Bool
False

-- | Find a "good" place to insert a bind in an indivisible segment.
-- This is the only place where we use heuristics.  The current
-- heuristic is to peel off the first group of independent statements
-- and put the bind after those.
splitSegment
  :: [(ExprLStmt GhcRn, FreeVars)]
  -> ( [(ExprLStmt GhcRn, FreeVars)]
     , [(ExprLStmt GhcRn, FreeVars)] )
splitSegment :: [(ExprLStmt GhcRn, FreeVars)]
-> ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)])
splitSegment [(ExprLStmt GhcRn, FreeVars)
one,(ExprLStmt GhcRn, FreeVars)
two] = ([(ExprLStmt GhcRn, FreeVars)
one],[(ExprLStmt GhcRn, FreeVars)
two])
  -- there is no choice when there are only two statements; this just saves
  -- some work in a common case.
splitSegment [(ExprLStmt GhcRn, FreeVars)]
stmts
  | Just ([(ExprLStmt GhcRn, FreeVars)]
lets,[(ExprLStmt GhcRn, FreeVars)]
binds,[(ExprLStmt GhcRn, FreeVars)]
rest) <- [(ExprLStmt GhcRn, FreeVars)]
-> Maybe
     ([(ExprLStmt GhcRn, FreeVars)], [(ExprLStmt GhcRn, FreeVars)],
      [(ExprLStmt GhcRn, FreeVars)])
forall (body :: * -> *).
[(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> Maybe
     ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)])
slurpIndependentStmts [(ExprLStmt GhcRn, FreeVars)]
stmts
  =  if Bool -> Bool
not ([(ExprLStmt GhcRn, FreeVars)] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [(ExprLStmt GhcRn, FreeVars)]
lets)
       then ([(ExprLStmt GhcRn, FreeVars)]
lets, [(ExprLStmt GhcRn, FreeVars)]
binds[(ExprLStmt GhcRn, FreeVars)]
-> [(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. [a] -> [a] -> [a]
++[(ExprLStmt GhcRn, FreeVars)]
rest)
       else ([(ExprLStmt GhcRn, FreeVars)]
lets[(ExprLStmt GhcRn, FreeVars)]
-> [(ExprLStmt GhcRn, FreeVars)] -> [(ExprLStmt GhcRn, FreeVars)]
forall a. [a] -> [a] -> [a]
++[(ExprLStmt GhcRn, FreeVars)]
binds, [(ExprLStmt GhcRn, FreeVars)]
rest)
  | Bool
otherwise
  = case [(ExprLStmt GhcRn, FreeVars)]
stmts of
      ((ExprLStmt GhcRn, FreeVars)
x:[(ExprLStmt GhcRn, FreeVars)]
xs) -> ([(ExprLStmt GhcRn, FreeVars)
x],[(ExprLStmt GhcRn, FreeVars)]
xs)
      [(ExprLStmt GhcRn, FreeVars)]
_other -> ([(ExprLStmt GhcRn, FreeVars)]
stmts,[])

slurpIndependentStmts
   :: [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
   -> Maybe ( [(LStmt GhcRn (Located (body GhcRn)), FreeVars)] -- LetStmts
            , [(LStmt GhcRn (Located (body GhcRn)), FreeVars)] -- BindStmts
            , [(LStmt GhcRn (Located (body GhcRn)), FreeVars)] )
slurpIndependentStmts :: forall (body :: * -> *).
[(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> Maybe
     ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)])
slurpIndependentStmts [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts = [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> FreeVars
-> [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
-> Maybe
     ([(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)],
      [(LStmt GhcRn (Located (body GhcRn)), FreeVars)])
forall {p :: Pass} {idR} {body} {idR} {body} {l}.
(CollectPass (GhcPass p),
 XBindStmt (GhcPass p) idR body ~ XBindStmt (GhcPass p) idR body,
 IdGhcP p ~ Name,
 XLetStmt (GhcPass p) idR body ~ XLetStmt (GhcPass p) idR body) =>
[(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> FreeVars
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> Maybe
     ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
go [] [] FreeVars
emptyNameSet [(LStmt GhcRn (Located (body GhcRn)), FreeVars)]
stmts
 where
  -- If we encounter a BindStmt that doesn't depend on a previous BindStmt
  -- in this group, then add it to the group. We have to be careful about
  -- strict patterns though; splitSegments expects that if we return Just
  -- then we have actually done some splitting. Otherwise it will go into
  -- an infinite loop (#14163).
  go :: [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> FreeVars
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> Maybe
     ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep FreeVars
bndrs ((L l
loc (BindStmt XBindStmt (GhcPass p) idR body
xbs LPat (GhcPass p)
pat body
body), FreeVars
fvs): [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
rest)
    | FreeVars -> FreeVars -> Bool
disjointNameSet FreeVars
bndrs FreeVars
fvs Bool -> Bool -> Bool
&& Bool -> Bool
not (LPat (GhcPass p) -> Bool
forall (p :: Pass). LPat (GhcPass p) -> Bool
isStrictPattern LPat (GhcPass p)
pat)
    = [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> FreeVars
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> Maybe
     ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets ((l
-> StmtLR (GhcPass p) idR body
-> GenLocated l (StmtLR (GhcPass p) idR body)
forall l e. l -> e -> GenLocated l e
L l
loc (XBindStmt (GhcPass p) idR body
-> LPat (GhcPass p) -> body -> StmtLR (GhcPass p) idR body
forall idL idR body.
XBindStmt idL idR body -> LPat idL -> body -> StmtLR idL idR body
BindStmt XBindStmt (GhcPass p) idR body
XBindStmt (GhcPass p) idR body
xbs LPat (GhcPass p)
pat body
body), FreeVars
fvs) (GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
forall a. a -> [a] -> [a]
: [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep)
         FreeVars
bndrs' [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
rest
    where bndrs' :: FreeVars
bndrs' = FreeVars
bndrs FreeVars -> FreeVars -> FreeVars
`unionNameSet` [Name] -> FreeVars
mkNameSet (LPat (GhcPass p) -> [IdP (GhcPass p)]
forall p. CollectPass p => LPat p -> [IdP p]
collectPatBinders LPat (GhcPass p)
pat)
  -- If we encounter a LetStmt that doesn't depend on a BindStmt in this
  -- group, then move it to the beginning, so that it doesn't interfere with
  -- grouping more BindStmts.
  -- TODO: perhaps we shouldn't do this if there are any strict bindings,
  -- because we might be moving evaluation earlier.
  go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep FreeVars
bndrs ((L l
loc (LetStmt XLetStmt (GhcPass p) idR body
noExtField LHsLocalBindsLR (GhcPass p) idR
binds), FreeVars
fvs) : [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
rest)
    | FreeVars -> FreeVars -> Bool
disjointNameSet FreeVars
bndrs FreeVars
fvs
    = [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> FreeVars
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> Maybe
     ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
go ((l
-> StmtLR (GhcPass p) idR body
-> GenLocated l (StmtLR (GhcPass p) idR body)
forall l e. l -> e -> GenLocated l e
L l
loc (XLetStmt (GhcPass p) idR body
-> LHsLocalBindsLR (GhcPass p) idR -> StmtLR (GhcPass p) idR body
forall idL idR body.
XLetStmt idL idR body
-> LHsLocalBindsLR idL idR -> StmtLR idL idR body
LetStmt XLetStmt (GhcPass p) idR body
XLetStmt (GhcPass p) idR body
noExtField LHsLocalBindsLR (GhcPass p) idR
binds), FreeVars
fvs) (GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
forall a. a -> [a] -> [a]
: [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets) [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep FreeVars
bndrs [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
rest
  go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
_ []  FreeVars
_ [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
_ = Maybe
  ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
   [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
   [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
forall a. Maybe a
Nothing
  go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
_ [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)
_] FreeVars
_ [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
_ = Maybe
  ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
   [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
   [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
forall a. Maybe a
Nothing
  go [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep FreeVars
_ [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
stmts = ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
 [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
 [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
-> Maybe
     ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)],
      [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)])
forall a. a -> Maybe a
Just ([(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
forall a. [a] -> [a]
reverse [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
lets, [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
-> [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
forall a. [a] -> [a]
reverse [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
indep, [(GenLocated l (StmtLR (GhcPass p) idR body), FreeVars)]
stmts)

-- | Build an ApplicativeStmt, and strip the "return" from the tail
-- if necessary.
--
-- For example, if we start with
--   do x <- E1; y <- E2; return (f x y)
-- then we get
--   do (E1[x] | E2[y]); f x y
--
-- the LastStmt in this case has the return removed, but we set the
-- flag on the LastStmt to indicate this, so that we can print out the
-- original statement correctly in error messages.  It is easier to do
-- it this way rather than try to ignore the return later in both the
-- typechecker and the desugarer (I tried it that way first!).
mkApplicativeStmt
  :: HsStmtContext GhcRn
  -> [ApplicativeArg GhcRn]             -- ^ The args
  -> Bool                               -- ^ True <=> need a join
  -> [ExprLStmt GhcRn]        -- ^ The body statements
  -> RnM ([ExprLStmt GhcRn], FreeVars)
mkApplicativeStmt :: HsStmtContext GhcRn
-> [ApplicativeArg GhcRn]
-> Bool
-> [ExprLStmt GhcRn]
-> RnM ([ExprLStmt GhcRn], FreeVars)
mkApplicativeStmt HsStmtContext GhcRn
ctxt [ApplicativeArg GhcRn]
args Bool
need_join [ExprLStmt GhcRn]
body_stmts
  = do { (SyntaxExprRn
fmap_op, FreeVars
fvs1) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
fmapName
       ; (SyntaxExprRn
ap_op, FreeVars
fvs2) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
apAName
       ; (Maybe SyntaxExprRn
mb_join, FreeVars
fvs3) <-
           if Bool
need_join then
             do { (SyntaxExprRn
join_op, FreeVars
fvs) <- HsStmtContext GhcRn -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDoStmtName HsStmtContext GhcRn
ctxt Name
joinMName
                ; (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExprRn -> Maybe SyntaxExprRn
forall a. a -> Maybe a
Just SyntaxExprRn
join_op, FreeVars
fvs) }
           else
             (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe SyntaxExprRn
forall a. Maybe a
Nothing, FreeVars
emptyNameSet)
       ; let applicative_stmt :: ExprLStmt GhcRn
applicative_stmt = StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> ExprLStmt GhcRn
forall e. e -> Located e
noLoc (StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> ExprLStmt GhcRn)
-> StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> ExprLStmt GhcRn
forall a b. (a -> b) -> a -> b
$ XApplicativeStmt GhcRn GhcRn (LHsExpr GhcRn)
-> [(SyntaxExpr GhcRn, ApplicativeArg GhcRn)]
-> Maybe (SyntaxExpr GhcRn)
-> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall idL idR body.
XApplicativeStmt idL idR body
-> [(SyntaxExpr idR, ApplicativeArg idL)]
-> Maybe (SyntaxExpr idR)
-> StmtLR idL idR body
ApplicativeStmt NoExtField
XApplicativeStmt GhcRn GhcRn (LHsExpr GhcRn)
noExtField
               ([SyntaxExprRn]
-> [ApplicativeArg GhcRn] -> [(SyntaxExprRn, ApplicativeArg GhcRn)]
forall a b. [a] -> [b] -> [(a, b)]
zip (SyntaxExprRn
fmap_op SyntaxExprRn -> [SyntaxExprRn] -> [SyntaxExprRn]
forall a. a -> [a] -> [a]
: SyntaxExprRn -> [SyntaxExprRn]
forall a. a -> [a]
repeat SyntaxExprRn
ap_op) [ApplicativeArg GhcRn]
args)
               Maybe (SyntaxExpr GhcRn)
Maybe SyntaxExprRn
mb_join
       ; ([ExprLStmt GhcRn], FreeVars) -> RnM ([ExprLStmt GhcRn], FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return ( ExprLStmt GhcRn
applicative_stmt ExprLStmt GhcRn -> [ExprLStmt GhcRn] -> [ExprLStmt GhcRn]
forall a. a -> [a] -> [a]
: [ExprLStmt GhcRn]
body_stmts
                , FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs3) }

-- | Given the statements following an ApplicativeStmt, determine whether
-- we need a @join@ or not, and remove the @return@ if necessary.
needJoin :: MonadNames
         -> [ExprLStmt GhcRn]
         -> (Bool, [ExprLStmt GhcRn])
needJoin :: MonadNames -> [ExprLStmt GhcRn] -> (Bool, [ExprLStmt GhcRn])
needJoin MonadNames
_monad_names [] = (Bool
False, [])  -- we're in an ApplicativeArg
needJoin MonadNames
monad_names  [L SrcSpan
loc (LastStmt XLastStmt GhcRn GhcRn (LHsExpr GhcRn)
_ LHsExpr GhcRn
e Maybe Bool
_ SyntaxExpr GhcRn
t)]
 | Just (LHsExpr GhcRn
arg, Bool
wasDollar) <- MonadNames -> LHsExpr GhcRn -> Maybe (LHsExpr GhcRn, Bool)
isReturnApp MonadNames
monad_names LHsExpr GhcRn
e =
       (Bool
False, [SrcSpan -> StmtLR GhcRn GhcRn (LHsExpr GhcRn) -> ExprLStmt GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (XLastStmt GhcRn GhcRn (LHsExpr GhcRn)
-> LHsExpr GhcRn
-> Maybe Bool
-> SyntaxExpr GhcRn
-> StmtLR GhcRn GhcRn (LHsExpr GhcRn)
forall idL idR body.
XLastStmt idL idR body
-> body -> Maybe Bool -> SyntaxExpr idR -> StmtLR idL idR body
LastStmt NoExtField
XLastStmt GhcRn GhcRn (LHsExpr GhcRn)
noExtField LHsExpr GhcRn
arg (Bool -> Maybe Bool
forall a. a -> Maybe a
Just Bool
wasDollar) SyntaxExpr GhcRn
t)])
needJoin MonadNames
_monad_names [ExprLStmt GhcRn]
stmts = (Bool
True, [ExprLStmt GhcRn]
stmts)

-- | @(Just e, False)@, if the expression is @return e@
--   @(Just e, True)@ if the expression is @return $ e@,
--   otherwise @Nothing@.
isReturnApp :: MonadNames
            -> LHsExpr GhcRn
            -> Maybe (LHsExpr GhcRn, Bool)
isReturnApp :: MonadNames -> LHsExpr GhcRn -> Maybe (LHsExpr GhcRn, Bool)
isReturnApp MonadNames
monad_names (L SrcSpan
_ (HsPar XPar GhcRn
_ LHsExpr GhcRn
expr)) = MonadNames -> LHsExpr GhcRn -> Maybe (LHsExpr GhcRn, Bool)
isReturnApp MonadNames
monad_names LHsExpr GhcRn
expr
isReturnApp MonadNames
monad_names (L SrcSpan
_ HsExpr GhcRn
e) = case HsExpr GhcRn
e of
  OpApp XOpApp GhcRn
_ LHsExpr GhcRn
l LHsExpr GhcRn
op LHsExpr GhcRn
r | LHsExpr GhcRn -> Bool
is_return LHsExpr GhcRn
l, LHsExpr GhcRn -> Bool
is_dollar LHsExpr GhcRn
op -> (LHsExpr GhcRn, Bool) -> Maybe (LHsExpr GhcRn, Bool)
forall a. a -> Maybe a
Just (LHsExpr GhcRn
r, Bool
True)
  HsApp XApp GhcRn
_ LHsExpr GhcRn
f LHsExpr GhcRn
arg  | LHsExpr GhcRn -> Bool
is_return LHsExpr GhcRn
f               -> (LHsExpr GhcRn, Bool) -> Maybe (LHsExpr GhcRn, Bool)
forall a. a -> Maybe a
Just (LHsExpr GhcRn
arg, Bool
False)
  HsExpr GhcRn
_otherwise -> Maybe (LHsExpr GhcRn, Bool)
forall a. Maybe a
Nothing
 where
  is_var :: (IdP p -> Bool) -> LHsExpr p -> Bool
is_var IdP p -> Bool
f (L SrcSpan
_ (HsPar XPar p
_ LHsExpr p
e)) = (IdP p -> Bool) -> LHsExpr p -> Bool
is_var IdP p -> Bool
f LHsExpr p
e
  is_var IdP p -> Bool
f (L SrcSpan
_ (HsAppType XAppTypeE p
_ LHsExpr p
e LHsWcType (NoGhcTc p)
_)) = (IdP p -> Bool) -> LHsExpr p -> Bool
is_var IdP p -> Bool
f LHsExpr p
e
  is_var IdP p -> Bool
f (L SrcSpan
_ (HsVar XVar p
_ (L SrcSpan
_ IdP p
r))) = IdP p -> Bool
f IdP p
r
       -- TODO: I don't know how to get this right for rebindable syntax
  is_var IdP p -> Bool
_ LHsExpr p
_ = Bool
False

  is_return :: LHsExpr GhcRn -> Bool
is_return = (IdP GhcRn -> Bool) -> LHsExpr GhcRn -> Bool
forall {p}. (IdP p -> Bool) -> LHsExpr p -> Bool
is_var (\IdP GhcRn
n -> Name
IdP GhcRn
n Name -> Name -> Bool
forall a. Eq a => a -> a -> Bool
== MonadNames -> Name
return_name MonadNames
monad_names
                         Bool -> Bool -> Bool
|| Name
IdP GhcRn
n Name -> Name -> Bool
forall a. Eq a => a -> a -> Bool
== MonadNames -> Name
pure_name MonadNames
monad_names)
  is_dollar :: LHsExpr GhcRn -> Bool
is_dollar = (IdP GhcRn -> Bool) -> LHsExpr GhcRn -> Bool
forall {p}. (IdP p -> Bool) -> LHsExpr p -> Bool
is_var (IdP GhcRn -> Unique -> Bool
forall a. Uniquable a => a -> Unique -> Bool
`hasKey` Unique
dollarIdKey)

{-
************************************************************************
*                                                                      *
\subsubsection{Errors}
*                                                                      *
************************************************************************
-}

checkEmptyStmts :: HsStmtContext GhcRn -> RnM ()
-- We've seen an empty sequence of Stmts... is that ok?
checkEmptyStmts :: HsStmtContext GhcRn -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkEmptyStmts HsStmtContext GhcRn
ctxt
  = Bool
-> IOEnv (Env TcGblEnv TcLclEnv) ()
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
unless (HsStmtContext GhcRn -> Bool
forall id. HsStmtContext id -> Bool
okEmpty HsStmtContext GhcRn
ctxt) (MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (HsStmtContext GhcRn -> MsgDoc
emptyErr HsStmtContext GhcRn
ctxt))

okEmpty :: HsStmtContext a -> Bool
okEmpty :: forall id. HsStmtContext id -> Bool
okEmpty (PatGuard {}) = Bool
True
okEmpty HsStmtContext a
_             = Bool
False

emptyErr :: HsStmtContext GhcRn -> SDoc
emptyErr :: HsStmtContext GhcRn -> MsgDoc
emptyErr (ParStmtCtxt {})   = String -> MsgDoc
text String
"Empty statement group in parallel comprehension"
emptyErr (TransStmtCtxt {}) = String -> MsgDoc
text String
"Empty statement group preceding 'group' or 'then'"
emptyErr HsStmtContext GhcRn
ctxt               = String -> MsgDoc
text String
"Empty" MsgDoc -> MsgDoc -> MsgDoc
<+> HsStmtContext GhcRn -> MsgDoc
forall id. Outputable (IdP id) => HsStmtContext id -> MsgDoc
pprStmtContext HsStmtContext GhcRn
ctxt

----------------------
checkLastStmt :: Outputable (body GhcPs) => HsStmtContext GhcRn
              -> LStmt GhcPs (Located (body GhcPs))
              -> RnM (LStmt GhcPs (Located (body GhcPs)))
checkLastStmt :: forall (body :: * -> *).
Outputable (body GhcPs) =>
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
checkLastStmt HsStmtContext GhcRn
ctxt lstmt :: LStmt GhcPs (Located (body GhcPs))
lstmt@(L SrcSpan
loc StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt)
  = case HsStmtContext GhcRn
ctxt of
      HsStmtContext GhcRn
ListComp  -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_comp
      HsStmtContext GhcRn
MonadComp -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_comp
      HsStmtContext GhcRn
ArrowExpr -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_do
      DoExpr{}  -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_do
      MDoExpr{} -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_do
      HsStmtContext GhcRn
_         -> RnM (LStmt GhcPs (Located (body GhcPs)))
check_other
  where
    check_do :: RnM (LStmt GhcPs (Located (body GhcPs)))
check_do    -- Expect BodyStmt, and change it to LastStmt
      = case StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt of
          BodyStmt XBodyStmt GhcPs GhcPs (Located (body GhcPs))
_ Located (body GhcPs)
e SyntaxExpr GhcPs
_ SyntaxExpr GhcPs
_ -> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (m :: * -> *) a. Monad m => a -> m a
return (SrcSpan
-> StmtLR GhcPs GhcPs (Located (body GhcPs))
-> LStmt GhcPs (Located (body GhcPs))
forall l e. l -> e -> GenLocated l e
L SrcSpan
loc (Located (body GhcPs) -> StmtLR GhcPs GhcPs (Located (body GhcPs))
forall (idR :: Pass) (bodyR :: * -> *) (idL :: Pass).
IsPass idR =>
Located (bodyR (GhcPass idR))
-> StmtLR
     (GhcPass idL) (GhcPass idR) (Located (bodyR (GhcPass idR)))
mkLastStmt Located (body GhcPs)
e))
          LastStmt {}      -> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (m :: * -> *) a. Monad m => a -> m a
return LStmt GhcPs (Located (body GhcPs))
lstmt   -- "Deriving" clauses may generate a
                                             -- LastStmt directly (unlike the parser)
          StmtLR GhcPs GhcPs (Located (body GhcPs))
_                -> do { MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (MsgDoc -> Int -> MsgDoc -> MsgDoc
hang MsgDoc
last_error Int
2 (StmtLR GhcPs GhcPs (Located (body GhcPs)) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt)); LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (m :: * -> *) a. Monad m => a -> m a
return LStmt GhcPs (Located (body GhcPs))
lstmt }
    last_error :: MsgDoc
last_error = (String -> MsgDoc
text String
"The last statement in" MsgDoc -> MsgDoc -> MsgDoc
<+> HsStmtContext GhcRn -> MsgDoc
forall id. Outputable (IdP id) => HsStmtContext id -> MsgDoc
pprAStmtContext HsStmtContext GhcRn
ctxt
                  MsgDoc -> MsgDoc -> MsgDoc
<+> String -> MsgDoc
text String
"must be an expression")

    check_comp :: RnM (LStmt GhcPs (Located (body GhcPs)))
check_comp  -- Expect LastStmt; this should be enforced by the parser!
      = case StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt of
          LastStmt {} -> LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (m :: * -> *) a. Monad m => a -> m a
return LStmt GhcPs (Located (body GhcPs))
lstmt
          StmtLR GhcPs GhcPs (Located (body GhcPs))
_           -> String -> MsgDoc -> RnM (LStmt GhcPs (Located (body GhcPs)))
forall a. HasCallStack => String -> MsgDoc -> a
pprPanic String
"checkLastStmt" (LStmt GhcPs (Located (body GhcPs)) -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr LStmt GhcPs (Located (body GhcPs))
lstmt)

    check_other :: RnM (LStmt GhcPs (Located (body GhcPs)))
check_other -- Behave just as if this wasn't the last stmt
      = do { HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (body :: * -> *).
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> IOEnv (Env TcGblEnv TcLclEnv) ()
checkStmt HsStmtContext GhcRn
ctxt LStmt GhcPs (Located (body GhcPs))
lstmt; LStmt GhcPs (Located (body GhcPs))
-> RnM (LStmt GhcPs (Located (body GhcPs)))
forall (m :: * -> *) a. Monad m => a -> m a
return LStmt GhcPs (Located (body GhcPs))
lstmt }

-- Checking when a particular Stmt is ok
checkStmt :: HsStmtContext GhcRn
          -> LStmt GhcPs (Located (body GhcPs))
          -> RnM ()
checkStmt :: forall (body :: * -> *).
HsStmtContext GhcRn
-> LStmt GhcPs (Located (body GhcPs))
-> IOEnv (Env TcGblEnv TcLclEnv) ()
checkStmt HsStmtContext GhcRn
ctxt (L SrcSpan
_ StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt)
  = do { DynFlags
dflags <- IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
       ; case DynFlags
-> HsStmtContext GhcRn
-> StmtLR GhcPs GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okStmt DynFlags
dflags HsStmtContext GhcRn
ctxt StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt of
           Validity
IsValid        -> () -> IOEnv (Env TcGblEnv TcLclEnv) ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
           NotValid MsgDoc
extra -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
addErr (MsgDoc
msg MsgDoc -> MsgDoc -> MsgDoc
$$ MsgDoc
extra) }
  where
   msg :: MsgDoc
msg = [MsgDoc] -> MsgDoc
sep [ String -> MsgDoc
text String
"Unexpected" MsgDoc -> MsgDoc -> MsgDoc
<+> StmtLR GhcPs GhcPs (Located (body GhcPs)) -> MsgDoc
forall (a :: Pass) body. Stmt (GhcPass a) body -> MsgDoc
pprStmtCat StmtLR GhcPs GhcPs (Located (body GhcPs))
stmt MsgDoc -> MsgDoc -> MsgDoc
<+> PtrString -> MsgDoc
ptext (String -> PtrString
sLit String
"statement")
             , String -> MsgDoc
text String
"in" MsgDoc -> MsgDoc -> MsgDoc
<+> HsStmtContext GhcRn -> MsgDoc
forall id. Outputable (IdP id) => HsStmtContext id -> MsgDoc
pprAStmtContext HsStmtContext GhcRn
ctxt ]

pprStmtCat :: Stmt (GhcPass a) body -> SDoc
pprStmtCat :: forall (a :: Pass) body. Stmt (GhcPass a) body -> MsgDoc
pprStmtCat (TransStmt {})     = String -> MsgDoc
text String
"transform"
pprStmtCat (LastStmt {})      = String -> MsgDoc
text String
"return expression"
pprStmtCat (BodyStmt {})      = String -> MsgDoc
text String
"body"
pprStmtCat (BindStmt {})      = String -> MsgDoc
text String
"binding"
pprStmtCat (LetStmt {})       = String -> MsgDoc
text String
"let"
pprStmtCat (RecStmt {})       = String -> MsgDoc
text String
"rec"
pprStmtCat (ParStmt {})       = String -> MsgDoc
text String
"parallel"
pprStmtCat (ApplicativeStmt {}) = String -> MsgDoc
forall a. String -> a
panic String
"pprStmtCat: ApplicativeStmt"

------------
emptyInvalid :: Validity  -- Payload is the empty document
emptyInvalid :: Validity
emptyInvalid = MsgDoc -> Validity
NotValid MsgDoc
Outputable.empty

okStmt, okDoStmt, okCompStmt, okParStmt
   :: DynFlags -> HsStmtContext GhcRn
   -> Stmt GhcPs (Located (body GhcPs)) -> Validity
-- Return Nothing if OK, (Just extra) if not ok
-- The "extra" is an SDoc that is appended to a generic error message

okStmt :: forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
  = case HsStmtContext GhcRn
ctxt of
      PatGuard {}        -> Stmt GhcPs (Located (body GhcPs)) -> Validity
forall (body :: * -> *).
Stmt GhcPs (Located (body GhcPs)) -> Validity
okPatGuardStmt Stmt GhcPs (Located (body GhcPs))
stmt
      ParStmtCtxt HsStmtContext GhcRn
ctxt   -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okParStmt  DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      DoExpr{}           -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okDoStmt   DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      MDoExpr{}          -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okDoStmt   DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      HsStmtContext GhcRn
ArrowExpr          -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okDoStmt   DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      HsStmtContext GhcRn
GhciStmtCtxt       -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okDoStmt   DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      HsStmtContext GhcRn
ListComp           -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okCompStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      HsStmtContext GhcRn
MonadComp          -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okCompStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
      TransStmtCtxt HsStmtContext GhcRn
ctxt -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt

-------------
okPatGuardStmt :: Stmt GhcPs (Located (body GhcPs)) -> Validity
okPatGuardStmt :: forall (body :: * -> *).
Stmt GhcPs (Located (body GhcPs)) -> Validity
okPatGuardStmt Stmt GhcPs (Located (body GhcPs))
stmt
  = case Stmt GhcPs (Located (body GhcPs))
stmt of
      BodyStmt {} -> Validity
IsValid
      BindStmt {} -> Validity
IsValid
      LetStmt {}  -> Validity
IsValid
      Stmt GhcPs (Located (body GhcPs))
_           -> Validity
emptyInvalid

-------------
okParStmt :: forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okParStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
  = case Stmt GhcPs (Located (body GhcPs))
stmt of
      LetStmt XLetStmt GhcPs GhcPs (Located (body GhcPs))
_ (L SrcSpan
_ (HsIPBinds {})) -> Validity
emptyInvalid
      Stmt GhcPs (Located (body GhcPs))
_                              -> DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt

----------------
okDoStmt :: forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okDoStmt DynFlags
dflags HsStmtContext GhcRn
ctxt Stmt GhcPs (Located (body GhcPs))
stmt
  = case Stmt GhcPs (Located (body GhcPs))
stmt of
       RecStmt {}
         | Extension
LangExt.RecursiveDo Extension -> DynFlags -> Bool
`xopt` DynFlags
dflags -> Validity
IsValid
         | HsStmtContext GhcRn
ArrowExpr <- HsStmtContext GhcRn
ctxt -> Validity
IsValid    -- Arrows allows 'rec'
         | Bool
otherwise         -> MsgDoc -> Validity
NotValid (String -> MsgDoc
text String
"Use RecursiveDo")
       BindStmt {} -> Validity
IsValid
       LetStmt {}  -> Validity
IsValid
       BodyStmt {} -> Validity
IsValid
       Stmt GhcPs (Located (body GhcPs))
_           -> Validity
emptyInvalid

----------------
okCompStmt :: forall (body :: * -> *).
DynFlags
-> HsStmtContext GhcRn
-> Stmt GhcPs (Located (body GhcPs))
-> Validity
okCompStmt DynFlags
dflags HsStmtContext GhcRn
_ Stmt GhcPs (Located (body GhcPs))
stmt
  = case Stmt GhcPs (Located (body GhcPs))
stmt of
       BindStmt {} -> Validity
IsValid
       LetStmt {}  -> Validity
IsValid
       BodyStmt {} -> Validity
IsValid
       ParStmt {}
         | Extension
LangExt.ParallelListComp Extension -> DynFlags -> Bool
`xopt` DynFlags
dflags -> Validity
IsValid
         | Bool
otherwise -> MsgDoc -> Validity
NotValid (String -> MsgDoc
text String
"Use ParallelListComp")
       TransStmt {}
         | Extension
LangExt.TransformListComp Extension -> DynFlags -> Bool
`xopt` DynFlags
dflags -> Validity
IsValid
         | Bool
otherwise -> MsgDoc -> Validity
NotValid (String -> MsgDoc
text String
"Use TransformListComp")
       RecStmt {}  -> Validity
emptyInvalid
       LastStmt {} -> Validity
emptyInvalid  -- Should not happen (dealt with by checkLastStmt)
       ApplicativeStmt {} -> Validity
emptyInvalid

---------
checkTupleSection :: [LHsTupArg GhcPs] -> RnM ()
checkTupleSection :: [LHsTupArg GhcPs] -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkTupleSection [LHsTupArg GhcPs]
args
  = do  { Bool
tuple_section <- Extension -> TcRnIf TcGblEnv TcLclEnv Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.TupleSections
        ; Bool -> MsgDoc -> IOEnv (Env TcGblEnv TcLclEnv) ()
checkErr ((LHsTupArg GhcPs -> Bool) -> [LHsTupArg GhcPs] -> Bool
forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
all LHsTupArg GhcPs -> Bool
forall id. LHsTupArg id -> Bool
tupArgPresent [LHsTupArg GhcPs]
args Bool -> Bool -> Bool
|| Bool
tuple_section) MsgDoc
msg }
  where
    msg :: MsgDoc
msg = String -> MsgDoc
text String
"Illegal tuple section: use TupleSections"

---------
sectionErr :: HsExpr GhcPs -> SDoc
sectionErr :: HsExpr GhcPs -> MsgDoc
sectionErr HsExpr GhcPs
expr
  = MsgDoc -> Int -> MsgDoc -> MsgDoc
hang (String -> MsgDoc
text String
"A section must be enclosed in parentheses")
       Int
2 (String -> MsgDoc
text String
"thus:" MsgDoc -> MsgDoc -> MsgDoc
<+> (MsgDoc -> MsgDoc
parens (HsExpr GhcPs -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr HsExpr GhcPs
expr)))

badIpBinds :: Outputable a => SDoc -> a -> SDoc
badIpBinds :: forall a. Outputable a => MsgDoc -> a -> MsgDoc
badIpBinds MsgDoc
what a
binds
  = MsgDoc -> Int -> MsgDoc -> MsgDoc
hang (String -> MsgDoc
text String
"Implicit-parameter bindings illegal in" MsgDoc -> MsgDoc -> MsgDoc
<+> MsgDoc
what)
         Int
2 (a -> MsgDoc
forall a. Outputable a => a -> MsgDoc
ppr a
binds)

---------

monadFailOp :: LPat GhcPs
            -> HsStmtContext GhcRn
            -> RnM (FailOperator GhcRn, FreeVars)
monadFailOp :: LPat GhcPs
-> HsStmtContext GhcRn -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
monadFailOp LPat GhcPs
pat HsStmtContext GhcRn
ctxt = do
    DynFlags
dflags <- IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
        -- If the pattern is irrefutable (e.g.: wildcard, tuple, ~pat, etc.)
        -- we should not need to fail.
    if | DynFlags -> LPat GhcPs -> Bool
forall (p :: Pass).
OutputableBndrId p =>
DynFlags -> LPat (GhcPass p) -> Bool
isIrrefutableHsPat DynFlags
dflags LPat GhcPs
pat -> (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe SyntaxExprRn
forall a. Maybe a
Nothing, FreeVars
emptyFVs)

        -- For non-monadic contexts (e.g. guard patterns, list
        -- comprehensions, etc.) we should not need to fail, or failure is handled in
        -- a different way. See Note [Failing pattern matches in Stmts].
       | Bool -> Bool
not (HsStmtContext GhcRn -> Bool
forall id. HsStmtContext id -> Bool
isMonadStmtContext HsStmtContext GhcRn
ctxt) -> (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe SyntaxExprRn
forall a. Maybe a
Nothing, FreeVars
emptyFVs)

       | Bool
otherwise -> HsStmtContext GhcRn -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
forall p.
HsStmtContext p -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
getMonadFailOp HsStmtContext GhcRn
ctxt

{-
Note [Monad fail : Rebindable syntax, overloaded strings]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Given the code
  foo x = do { Just y <- x; return y }

we expect it to desugar as
  foo x = x >>= \r -> case r of
                        Just y  -> return y
                        Nothing -> fail "Pattern match error"

But with RebindableSyntax and OverloadedStrings, we really want
it to desugar thus:
  foo x = x >>= \r -> case r of
                        Just y  -> return y
                        Nothing -> fail (fromString "Patterm match error")

So, in this case, we synthesize the function
  \x -> fail (fromString x)

(rather than plain 'fail') for the 'fail' operation. This is done in
'getMonadFailOp'.

Similarly with QualifiedDo and OverloadedStrings, we also want to desugar
using fromString:

  foo x = M.do { Just y <- x; return y }

  ===>

  foo x = x M.>>= \r -> case r of
                        Just y  -> return y
                        Nothing -> M.fail (fromString "Pattern match error")

-}
getMonadFailOp :: HsStmtContext p -> RnM (FailOperator GhcRn, FreeVars) -- Syntax expr fail op
getMonadFailOp :: forall p.
HsStmtContext p -> RnM (Maybe (SyntaxExpr GhcRn), FreeVars)
getMonadFailOp HsStmtContext p
ctxt
 = do { Bool
xOverloadedStrings <- (DynFlags -> Bool)
-> IOEnv (Env TcGblEnv TcLclEnv) DynFlags
-> TcRnIf TcGblEnv TcLclEnv Bool
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (Extension -> DynFlags -> Bool
xopt Extension
LangExt.OverloadedStrings) IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
      ; Bool
xRebindableSyntax <- (DynFlags -> Bool)
-> IOEnv (Env TcGblEnv TcLclEnv) DynFlags
-> TcRnIf TcGblEnv TcLclEnv Bool
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (Extension -> DynFlags -> Bool
xopt Extension
LangExt.RebindableSyntax) IOEnv (Env TcGblEnv TcLclEnv) DynFlags
forall (m :: * -> *). HasDynFlags m => m DynFlags
getDynFlags
      ; (SyntaxExprRn
fail, FreeVars
fvs) <- Bool
-> Bool -> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
reallyGetMonadFailOp Bool
xRebindableSyntax Bool
xOverloadedStrings
      ; (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExprRn -> Maybe SyntaxExprRn
forall a. a -> Maybe a
Just SyntaxExprRn
fail, FreeVars
fvs)
      }
  where
    isQualifiedDo :: Bool
isQualifiedDo = Maybe ModuleName -> Bool
forall a. Maybe a -> Bool
isJust (HsStmtContext p -> Maybe ModuleName
forall p. HsStmtContext p -> Maybe ModuleName
qualifiedDoModuleName_maybe HsStmtContext p
ctxt)

    reallyGetMonadFailOp :: Bool
-> Bool -> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
reallyGetMonadFailOp Bool
rebindableSyntax Bool
overloadedStrings
      | (Bool
isQualifiedDo Bool -> Bool -> Bool
|| Bool
rebindableSyntax) Bool -> Bool -> Bool
&& Bool
overloadedStrings = do
        (HsExpr GhcRn
failExpr, FreeVars
failFvs) <- HsStmtContext p -> Name -> TcM (HsExpr GhcRn, FreeVars)
forall p. HsStmtContext p -> Name -> TcM (HsExpr GhcRn, FreeVars)
lookupQualifiedDoExpr HsStmtContext p
ctxt Name
failMName
        (HsExpr GhcRn
fromStringExpr, FreeVars
fromStringFvs) <- Name -> TcM (HsExpr GhcRn, FreeVars)
lookupSyntaxExpr Name
fromStringName
        let arg_lit :: OccName
arg_lit = String -> OccName
mkVarOcc String
"arg"
        Name
arg_name <- OccName -> RnM Name
forall gbl lcl. OccName -> TcRnIf gbl lcl Name
newSysName OccName
arg_lit
        let arg_syn_expr :: LHsExpr GhcRn
arg_syn_expr = IdP GhcRn -> LHsExpr GhcRn
forall (id :: Pass). IdP (GhcPass id) -> LHsExpr (GhcPass id)
nlHsVar Name
IdP GhcRn
arg_name
            LHsExpr GhcRn
body :: LHsExpr GhcRn =
              LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn
forall (id :: Pass).
IsPass id =>
LHsExpr (GhcPass id)
-> LHsExpr (GhcPass id) -> LHsExpr (GhcPass id)
nlHsApp (HsExpr GhcRn -> LHsExpr GhcRn
forall e. e -> Located e
noLoc HsExpr GhcRn
failExpr)
                      (LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn
forall (id :: Pass).
IsPass id =>
LHsExpr (GhcPass id)
-> LHsExpr (GhcPass id) -> LHsExpr (GhcPass id)
nlHsApp (HsExpr GhcRn -> LHsExpr GhcRn
forall e. e -> Located e
noLoc (HsExpr GhcRn -> LHsExpr GhcRn) -> HsExpr GhcRn -> LHsExpr GhcRn
forall a b. (a -> b) -> a -> b
$ HsExpr GhcRn
fromStringExpr) LHsExpr GhcRn
arg_syn_expr)
        let HsExpr GhcRn
failAfterFromStringExpr :: HsExpr GhcRn =
              LHsExpr GhcRn -> HsExpr GhcRn
forall l e. GenLocated l e -> e
unLoc (LHsExpr GhcRn -> HsExpr GhcRn) -> LHsExpr GhcRn -> HsExpr GhcRn
forall a b. (a -> b) -> a -> b
$ [LPat GhcRn] -> LHsExpr GhcRn -> LHsExpr GhcRn
forall (p :: Pass).
(IsPass p, XMG (GhcPass p) (LHsExpr (GhcPass p)) ~ NoExtField) =>
[LPat (GhcPass p)] -> LHsExpr (GhcPass p) -> LHsExpr (GhcPass p)
mkHsLam [Pat GhcRn -> Located (Pat GhcRn)
forall e. e -> Located e
noLoc (Pat GhcRn -> Located (Pat GhcRn))
-> Pat GhcRn -> Located (Pat GhcRn)
forall a b. (a -> b) -> a -> b
$ XVarPat GhcRn -> Located (IdP GhcRn) -> Pat GhcRn
forall p. XVarPat p -> Located (IdP p) -> Pat p
VarPat NoExtField
XVarPat GhcRn
noExtField (Located (IdP GhcRn) -> Pat GhcRn)
-> Located (IdP GhcRn) -> Pat GhcRn
forall a b. (a -> b) -> a -> b
$ Name -> Located Name
forall e. e -> Located e
noLoc Name
arg_name] LHsExpr GhcRn
body
        let SyntaxExpr GhcRn
failAfterFromStringSynExpr :: SyntaxExpr GhcRn =
              HsExpr GhcRn -> SyntaxExprRn
mkSyntaxExpr HsExpr GhcRn
failAfterFromStringExpr
        (SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (SyntaxExprRn, FreeVars)
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExpr GhcRn
SyntaxExprRn
failAfterFromStringSynExpr, FreeVars
failFvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fromStringFvs)
      | Bool
otherwise = HsStmtContext p -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
forall p.
HsStmtContext p -> Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupQualifiedDo HsStmtContext p
ctxt Name
failMName

-- Rebinding 'if's to 'ifThenElse' applications.
--
-- See Note [Rebindable syntax and HsExpansion]
rebindIf
  :: Located Name  -- 'Name' for the 'ifThenElse' function we will rebind to
  -> LHsExpr GhcRn -- renamed condition
  -> LHsExpr GhcRn -- renamed true branch
  -> LHsExpr GhcRn -- renamed false branch
  -> HsExpr GhcRn  -- rebound if expression
rebindIf :: Located Name
-> LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
rebindIf Located Name
ifteName LHsExpr GhcRn
p LHsExpr GhcRn
b1 LHsExpr GhcRn
b2 =
  let ifteOrig :: HsExpr GhcRn
ifteOrig = XIf GhcRn
-> LHsExpr GhcRn -> LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn
forall p. XIf p -> LHsExpr p -> LHsExpr p -> LHsExpr p -> HsExpr p
HsIf NoExtField
XIf GhcRn
noExtField LHsExpr GhcRn
p LHsExpr GhcRn
b1 LHsExpr GhcRn
b2
      ifteFun :: LHsExpr GhcRn
ifteFun  = SrcSpan -> HsExpr GhcRn -> LHsExpr GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
generatedSrcSpan (XVar GhcRn -> Located (IdP GhcRn) -> HsExpr GhcRn
forall p. XVar p -> Located (IdP p) -> HsExpr p
HsVar NoExtField
XVar GhcRn
noExtField Located Name
Located (IdP GhcRn)
ifteName)
                 -- ifThenElse var
      ifteApp :: LHsExpr GhcRn
ifteApp  = (LHsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn -> LHsExpr GhcRn)
-> LHsExpr GhcRn -> [LHsExpr GhcRn] -> LHsExpr GhcRn
forall (id :: Pass).
(LHsExpr (GhcPass id)
 -> LHsExpr (GhcPass id)
 -> HsExpr (GhcPass id)
 -> LHsExpr (GhcPass id))
-> LHsExpr (GhcPass id)
-> [LHsExpr (GhcPass id)]
-> LHsExpr (GhcPass id)
mkHsAppsWith (\LHsExpr GhcRn
_ LHsExpr GhcRn
_ HsExpr GhcRn
e -> SrcSpan -> HsExpr GhcRn -> LHsExpr GhcRn
forall l e. l -> e -> GenLocated l e
L SrcSpan
generatedSrcSpan HsExpr GhcRn
e)
                              LHsExpr GhcRn
ifteFun
                              [LHsExpr GhcRn
p, LHsExpr GhcRn
b1, LHsExpr GhcRn
b2]
                 -- desugared_if_expr =
                 --   ifThenElse desugared_predicate
                 --              desugared_true_branch
                 --              desugared_false_branch
  in (HsExpansion (HsExpr GhcRn) (HsExpr GhcRn) -> HsExpr GhcRn)
-> HsExpr GhcRn -> HsExpr GhcRn -> HsExpr GhcRn
forall a b. (HsExpansion a b -> b) -> a -> b -> b
mkExpanded HsExpansion (HsExpr GhcRn) (HsExpr GhcRn) -> HsExpr GhcRn
forall p. XXExpr p -> HsExpr p
XExpr HsExpr GhcRn
ifteOrig (LHsExpr GhcRn -> HsExpr GhcRn
forall l e. GenLocated l e -> e
unLoc LHsExpr GhcRn
ifteApp)
     -- (source_if_expr, desugared_if_expr)