Safe Haskell	Safe-Inferred
Language	Haskell2010

GHC.Utils.FV

Contents

Deterministic free vars computations
Running the computations
- Manipulating those computations

Description

Utilities for efficiently and deterministically computing free variables.

Synopsis

type FV = InterestingVarFun -> VarSet -> VarAcc -> VarAcc
type InterestingVarFun = Var -> Bool
fvVarList :: FV -> [Var]
fvVarSet :: FV -> VarSet
fvDVarSet :: FV -> DVarSet
unitFV :: Id -> FV
emptyFV :: FV
mkFVs :: [Var] -> FV
unionFV :: FV -> FV -> FV
unionsFV :: [FV] -> FV
delFV :: Var -> FV -> FV
delFVs :: VarSet -> FV -> FV
filterFV :: InterestingVarFun -> FV -> FV
mapUnionFV :: (a -> FV) -> [a] -> FV

Deterministic free vars computations

type FV = InterestingVarFun -> VarSet -> VarAcc -> VarAcc Source #

type InterestingVarFun = Var -> Bool Source #

Predicate on possible free variables: returns True iff the variable is interesting

Running the computations

fvVarList :: FV -> [Var] Source #

Run a free variable computation, returning a list of distinct free variables in deterministic order.

fvVarSet :: FV -> VarSet Source #

Run a free variable computation, returning a non-deterministic set of free variables. Don't use if the set will be later converted to a list and the order of that list will impact the generated code.

fvDVarSet :: FV -> DVarSet Source #

Run a free variable computation, returning a deterministic set of free variables. Note that this is just a wrapper around the version that returns a deterministic list. If you need a list you should use fvVarList.