HscTypes

A minimal implementation of a GhcMonad. If you need a custom monad, e.g., to maintain additional state consider wrapping this monad or using GhcT.

Constructors

Ghc

unGhc :: Session -> IO a

Instances

newtype GhcT m a

A monad transformer to add GHC specific features to another monad.

Note that the wrapped monad must support IO and handling of exceptions.

Constructors

GhcT

unGhcT :: Session -> m a

Instances

Monad m => Monad (GhcT m)

Functor m => Functor (GhcT m)

MonadIO m => MonadIO (GhcT m)

ExceptionMonad m => ExceptionMonad (GhcT m)

(Functor m, ExceptionMonad m, MonadIO m) => GhcMonad (GhcT m)

MonadIO m => WarnLogMonad (GhcT m)

liftGhcT :: Monad m => m a -> GhcT m a

class (Functor m, MonadIO m, WarnLogMonad m, ExceptionMonad m) => GhcMonad m where

A monad that has all the features needed by GHC API calls.

In short, a GHC monad

allows embedding of IO actions,
can log warnings,
allows handling of (extensible) exceptions, and
maintains a current session.

If you do not use Ghc or GhcT, make sure to call GHC.initGhcMonad before any call to the GHC API functions can occur.

Methods

getSession :: m HscEnv

setSession :: HscEnv -> m ()

Instances

GhcMonad Ghc

GhcMonad GHCi

(Functor m, ExceptionMonad m, MonadIO m) => GhcMonad (GhcT m)

class Monad m => WarnLogMonad m where

A monad that allows logging of warnings.

Methods

setWarnings :: WarningMessages -> m ()

getWarnings :: m WarningMessages

Instances

WarnLogMonad Ghc

WarnLogMonad GHCi

MonadIO m => WarnLogMonad (GhcT m)

liftIO :: MonadIO m => IO a -> m a

ioMsgMaybe :: GhcMonad m => IO (Messages, Maybe a) -> m a

Lift an IO action returning errors messages into a GhcMonad.

In order to reduce dependencies to other parts of the compiler, functions outside the main parts of GHC return warnings and errors as a parameter and signal success via by wrapping the result in a Maybe type. This function logs the returned warnings and propagates errors as exceptions (of type SourceError).

This function assumes the following invariants:

1. If the second result indicates success (is of the form 'Just x'), there must be no error messages in the first result.

2. If there are no error messages, but the second result indicates failure there should be warnings in the first result. That is, if the action failed, it must have been due to the warnings (i.e., -Werror).

ioMsg :: GhcMonad m => IO (Messages, a) -> m a

Lift a non-failing IO action into a GhcMonad.

Like ioMsgMaybe, but assumes that the action will never return any error messages.

logWarnings :: WarnLogMonad m => WarningMessages -> m ()

clearWarnings :: WarnLogMonad m => m ()

Clear the log of Warnings.

hasWarnings :: WarnLogMonad m => m Bool

Returns true if there were any warnings.

data SourceError

A source error is an error that is caused by one or more errors in the source code. A SourceError is thrown by many functions in the compilation pipeline. Inside GHC these errors are merely printed via log_action, but API clients may treat them differently, for example, insert them into a list box. If you want the default behaviour, use the idiom:

 handleSourceError printExceptionAndWarnings $ do
   ... api calls that may fail ...

The SourceErrors error messages can be accessed via srcErrorMessages. This list may be empty if the compiler failed due to -Werror (Opt_WarnIsError).

See printExceptionAndWarnings for more information on what to take care of when writing a custom error handler.

Instances

Show SourceError

Typeable SourceError

Exception SourceError

data GhcApiError

XXX: what exactly is an API error?

Instances

Show GhcApiError

Typeable GhcApiError

Exception GhcApiError

mkSrcErr :: ErrorMessages -> SourceError

srcErrorMessages :: SourceError -> ErrorMessages

mkApiErr :: SDoc -> GhcApiError

throwOneError :: MonadIO m => ErrMsg -> m ab

handleSourceError

:: ExceptionMonad m
=> SourceError -> m a	exception handler
-> m a	action to perform
-> m a
Perform the given action and call the exception handler if the action throws a `SourceError`. See `SourceError` for more information.

reflectGhc :: Ghc a -> Session -> IO a

Reflect a computation in the Ghc monad into the IO monad.

You can use this to call functions returning an action in the Ghc monad inside an IO action. This is needed for some (too restrictive) callback arguments of some library functions:

 libFunc :: String -> (Int -> IO a) -> IO a
 ghcFunc :: Int -> Ghc a

 ghcFuncUsingLibFunc :: String -> Ghc a -> Ghc a
 ghcFuncUsingLibFunc str =
   reifyGhc $ \s ->
     libFunc $ \i -> do
       reflectGhc (ghcFunc i) s

reifyGhc :: (Session -> IO a) -> Ghc a

Sessions and compilation state

data Session

The Session is a handle to the complete state of a compilation session. A compilation session consists of a set of modules constituting the current program or library, the context for interactive evaluation, and various caches.

Constructors

Session !(IORef HscEnv) !(IORef WarningMessages)

withSession :: GhcMonad m => (HscEnv -> m a) -> m a

Call the argument with the current session.

modifySession :: GhcMonad m => (HscEnv -> HscEnv) -> m ()

Set the current session to the result of applying the current session to the argument.

data HscEnv

HscEnv is like Session, except that some of the fields are immutable. An HscEnv is used to compile a single module from plain Haskell source code (after preprocessing) to either C, assembly or C--. Things like the module graph don't change during a single compilation.

Historical note: "hsc" used to be the name of the compiler binary, when there was a separate driver and compiler. To compile a single module, the driver would invoke hsc on the source code... so nowadays we think of hsc as the layer of the compiler that deals with compiling a single module.

Constructors

HscEnv

hsc_dflags :: DynFlags	The dynamic flag settings
hsc_targets :: [Target]	The targets (or roots) of the current session
hsc_mod_graph :: ModuleGraph	The module graph of the current session
hsc_IC :: InteractiveContext	The context for evaluating interactive statements
hsc_HPT :: HomePackageTable	The home package table describes already-compiled home-package modules, excluding the module we are compiling right now. (In one-shot mode the current module is the only home-package module, so hsc_HPT is empty. All other modules count as "external-package" modules. However, even in GHCi mode, hi-boot interfaces are demand-loaded into the external-package table.) `hsc_HPT` is not mutable because we only demand-load external packages; the home package is eagerly loaded, module by module, by the compilation manager. The HPT may contain modules compiled earlier by `--make` but not actually below the current module in the dependency graph.
hsc_EPS :: !!(IORef ExternalPackageState)	Information about the currently loaded external packages. This is mutable because packages will be demand-loaded during a compilation run as required.
hsc_NC :: !!(IORef NameCache)	As with `hsc_EPS`, this is side-effected by compiling to reflect sucking in interface files. They cache the state of external interface files, in effect.
hsc_FC :: !!(IORef FinderCache)	The cached result of performing finding in the file system
hsc_MLC :: !!(IORef ModLocationCache)	This caches the location of modules, so we don't have to search the filesystem multiple times. See also `hsc_FC`.
hsc_OptFuel :: OptFuelState	Settings to control the use of "optimization fuel": by limiting the number of transformations, we can use binary search to help find compiler bugs.
hsc_type_env_var :: Maybe (Module, IORef TypeEnv)	Used for one-shot compilation only, to initialise the IfGblEnv. See TcRnTypes.tcg_type_env_var for TcRunTypes.TcGblEnv
hsc_global_rdr_env :: GlobalRdrEnv	A mapping from `RdrName`s that are in global scope during the compilation of the current file to more detailed information about those names. Not necessarily just the names directly imported by the module being compiled!
hsc_global_type_env :: TypeEnv	Typing information about all those things in global scope. Not necessarily just the things directly imported by the module being compiled!

hscEPS :: HscEnv -> IO ExternalPackageState

type FinderCache = ModuleNameEnv FindResult

The FinderCache maps home module names to the result of searching for that module. It records the results of searching for modules along the search path. On :load, we flush the entire contents of this cache.

Although the FinderCache range is FindResult for convenience , in fact it will only ever contain Found or NotFound entries.

data FindResult

The result of searching for an imported module.

Constructors

Found ModLocation Module	The module was found
NoPackage PackageId	The requested package was not found
FoundMultiple [PackageId]	_Error_: both in multiple packages
PackageHidden PackageId	For an explicit source import, the package containing the module is not exposed.
ModuleHidden PackageId	For an explicit source import, the package containing the module is exposed, but the module itself is hidden.
NotFound [FilePath] (Maybe PackageId)	The module was not found, the specified places were searched
NotFoundInPackage PackageId	The module was not found in this package

type ModLocationCache = ModuleEnv ModLocation

Cache that remembers where we found a particular module. Contains both home modules and package modules. On :load, only home modules are purged from this cache.

data Target

A compilation target.

A target may be supplied with the actual text of the module. If so, use this instead of the file contents (this is for use in an IDE where the file hasn't been saved by the user yet).

Constructors

Target

targetId :: TargetId	module or filename
targetAllowObjCode :: Bool	object code allowed?
targetContents :: Maybe (StringBuffer, ClockTime)	in-memory text buffer?

Instances

Outputable Target

data TargetId

Constructors

TargetModule ModuleName	A module name: search for the file
TargetFile FilePath (Maybe Phase)	A filename: preprocess & parse it to find the module name. If specified, the Phase indicates how to compile this file (which phase to start from). Nothing indicates the starting phase should be determined from the suffix of the filename.

Instances

Eq TargetId

Outputable TargetId

pprTarget :: Target -> SDoc

pprTargetId :: TargetId -> SDoc

type ModuleGraph = [ModSummary]

A ModuleGraph contains all the nodes from the home package (only). There will be a node for each source module, plus a node for each hi-boot module.

The graph is not necessarily stored in topologically-sorted order.

emptyMG :: ModuleGraph

Information about modules

data ModDetails

The ModDetails is essentially a cache for information in the ModIface for home modules only. Information relating to packages will be loaded into global environments in ExternalPackageState.

Constructors

ModDetails

md_exports :: [AvailInfo]
md_types :: !TypeEnv	Local type environment for this particular module
md_insts :: ![Instance]	DFunIds for the instances in this module
md_fam_insts :: ![FamInst]
md_rules :: ![CoreRule]	Domain may include `Id`s from other modules
md_vect_info :: !VectInfo	Module vectorisation information

emptyModDetails :: ModDetails

data ModGuts

A ModGuts is carried through the compiler, accumulating stuff as it goes There is only one ModGuts at any time, the one for the module being compiled right now. Once it is compiled, a ModIface and ModDetails are extracted and the ModGuts is dicarded.

Constructors

ModGuts

mg_module :: !Module	Module being compiled
mg_boot :: IsBootInterface	Whether it's an hs-boot module
mg_exports :: ![AvailInfo]	What it exports
mg_deps :: !Dependencies	What it depends on, directly or otherwise
mg_dir_imps :: !ImportedMods	Directly-imported modules; used to generate initialisation code
mg_used_names :: !NameSet	What the module needed (used in MkIface.mkIface)
mg_rdr_env :: !GlobalRdrEnv	Top-level lexical environment
mg_fix_env :: !FixityEnv	Fixities declared in this module TODO: I'm unconvinced this is actually used anywhere
mg_types :: !TypeEnv	Types declared in this module
mg_insts :: ![Instance]	Class instances declared in this module
mg_fam_insts :: ![FamInst]	Family instances declared in this module
mg_rules :: ![CoreRule]	Before the core pipeline starts, contains rules declared in this module. After the core pipeline starts, it is changed to contain all known rules for those things imported
mg_binds :: ![CoreBind]	Bindings for this module
mg_foreign :: !ForeignStubs	Foreign exports declared in this module
mg_warns :: !Warnings	Warnings declared in the module
mg_hpc_info :: !HpcInfo	Coverage tick boxes in the module
mg_modBreaks :: !ModBreaks	Breakpoints for the module
mg_vect_info :: !VectInfo	Pool of vectorised declarations in the module
mg_inst_env :: InstEnv	Class instance environment from home-package modules (including this one); c.f. tcg_inst_env
mg_fam_inst_env :: FamInstEnv	Type-family instance enviroment for home-package modules (including this one); c.f. tcg_fam_inst_env

data CoreModule

A CoreModule consists of just the fields of a ModGuts that are needed for the GHC.compileToCoreModule interface.

Constructors

CoreModule

cm_module :: !Module	Module name
cm_types :: !TypeEnv	Type environment for types declared in this module
cm_binds :: [CoreBind]	Declarations
cm_imports :: ![Module]	Imports

Instances

Outputable CoreModule

data CgGuts

A restricted form of ModGuts for code generation purposes

Constructors

CgGuts

cg_module :: !Module	Module being compiled
cg_tycons :: [TyCon]	Algebraic data types (including ones that started life as classes); generate constructors and info tables. Includes newtypes, just for the benefit of External Core
cg_binds :: [CoreBind]	The tidied main bindings, including previously-implicit bindings for record and class selectors, and data construtor wrappers. But not data constructor workers; reason: we we regard them as part of the code-gen of tycons
cg_dir_imps :: ![Module]	Directly-imported modules; used to generate initialisation code
cg_foreign :: !ForeignStubs	Foreign export stubs
cg_dep_pkgs :: ![PackageId]	Dependent packages, used to generate #includes for C code gen
cg_hpc_info :: !HpcInfo	Program coverage tick box information
cg_modBreaks :: !ModBreaks	Module breakpoints

data ForeignStubs

Foreign export stubs

Constructors

NoStubs

We don't have any stubs

ForeignStubs SDoc SDoc

There are some stubs. Parameters:

1) Header file prototypes for foreign exported functions

2) C stubs to use when calling foreign exported functions

type ImportedMods = ModuleEnv [(ModuleName, Bool, SrcSpan)]

Records the modules directly imported by a module for extracting e.g. usage information

data ModSummary

A single node in a 'ModuleGraph. The nodes of the module graph are one of:

A regular Haskell source module
A hi-boot source module
An external-core source module

Constructors

ModSummary

ms_mod :: Module	Identity of the module
ms_hsc_src :: HscSource	The module source either plain Haskell, hs-boot or external core
ms_location :: ModLocation	Location of the various files belonging to the module
ms_hs_date :: ClockTime	Timestamp of source file
ms_obj_date :: Maybe ClockTime	Timestamp of object, if we have one
ms_srcimps :: [Located ModuleName]	Source imports of the module
ms_imps :: [Located ModuleName]	Non-source imports of the module
ms_hspp_file :: FilePath	Filename of preprocessed source file
ms_hspp_opts :: DynFlags	Cached flags from `OPTIONS`, `INCLUDE` and `LANGUAGE` pragmas in the modules source code
ms_hspp_buf :: Maybe StringBuffer	The actual preprocessed source, if we have it

Instances

Outputable ModSummary

ms_mod_name :: ModSummary -> ModuleName

showModMsg :: HscTarget -> Bool -> ModSummary -> String

isBootSummary :: ModSummary -> Bool

Did this ModSummary originate from a hs-boot file?

msHiFilePath :: ModSummary -> FilePath

Information about the module being compiled

data HscSource

Constructors

HsSrcFile
HsBootFile
ExtCoreFile

Instances

Eq HscSource

Ord HscSource

Show HscSource

isHsBoot :: HscSource -> Bool

hscSourceString :: HscSource -> String

State relating to modules in this package

type HomePackageTable = ModuleNameEnv HomeModInfo

Helps us find information about modules in the home package

data HomeModInfo

Information about modules in the package being compiled

Constructors

HomeModInfo

hm_iface :: !ModIface The basic loaded interface file: every loaded module has one of these, even if it is imported from another package

hm_details :: !ModDetails Extra information that has been created from the ModIface for the module, typically during typechecking

hm_linkable :: !(Maybe Linkable)

The actual artifact we would like to link to access things in this module.

hm_linkable might be Nothing:

1. If this is an .hs-boot module

2. Temporarily during compilation if we pruned away the old linkable because it was out of date.

After a complete compilation (GHC.load), all hm_linkable fields in the HomePackageTable will be Just.

When re-linking a module (HscMain.HscNoRecomp), we construct the HomeModInfo by building a new ModDetails from the old ModIface (only).

emptyHomePackageTable :: HomePackageTable

hptInstances :: HscEnv -> (ModuleName -> Bool) -> ([Instance], [FamInst])

Find all the instance declarations (of classes and families) that are in modules imported by this one, directly or indirectly, and are in the Home Package Table. This ensures that we don't see instances from modules --make compiled before this one, but which are not below this one.

hptRules :: HscEnv -> [(ModuleName, IsBootInterface)] -> [CoreRule]

Get rules from modules "below" this one (in the dependency sense)

hptVectInfo :: HscEnv -> VectInfo

Get the combined VectInfo of all modules in the home package table. In contrast to instances and rules, we don't care whether the modules are "below" us in the dependency sense. The VectInfo of those modules not "below" us does not affect the compilation of the current module.

State relating to known packages

data ExternalPackageState

Information about other packages that we have slurped in by reading their interface files

Constructors

EPS

eps_is_boot :: !(ModuleNameEnv (ModuleName, IsBootInterface))	In OneShot mode (only), home-package modules accumulate in the external package state, and are sucked in lazily. For these home-pkg modules (only) we need to record which are boot modules. We set this field after loading all the explicitly-imported interfaces, but before doing anything else The `ModuleName` part is not necessary, but it's useful for debug prints, and it's convenient because this field comes direct from TcRnTypes.imp_dep_mods
eps_PIT :: !PackageIfaceTable	The `ModIface`s for modules in external packages whose interfaces we have opened. The declarations in these interface files are held in the eps_decls, `eps_inst_env`, `eps_fam_inst_env` and eps_rules fields of this record, not in the `mi_decls` fields of the interface we have sucked in. What is in the PIT is: The Module Fingerprint info Its exports Fixities Deprecations and warnings
eps_PTE :: !PackageTypeEnv	Result of typechecking all the external package interface files we have sucked in. The domain of the mapping is external-package modules
eps_inst_env :: !PackageInstEnv	The total `InstEnv` accumulated from all the external-package modules
eps_fam_inst_env :: !PackageFamInstEnv	The total `FamInstEnv` accumulated from all the external-package modules
eps_rule_base :: !PackageRuleBase	The total RuleEnv accumulated from all the external-package modules
eps_vect_info :: !PackageVectInfo	The total `VectInfo` accumulated from all the external-package modules
eps_mod_fam_inst_env :: !(ModuleEnv FamInstEnv)	The family instances accumulated from external packages, keyed off the module that declared them
eps_stats :: !EpsStats	Stastics about what was loaded from external packages

data EpsStats

Accumulated statistics about what we are putting into the ExternalPackageState. "In" means stuff that is just read from interface files, "Out" means actually sucked in and type-checked

Constructors

EpsStats

n_ifaces_in :: !Int
n_decls_in :: !Int
n_decls_out :: !Int
n_rules_in :: !Int
n_rules_out :: !Int
n_insts_in :: !Int
n_insts_out :: !Int

addEpsInStats :: EpsStats -> Int -> Int -> Int -> EpsStats

Add stats for one newly-read interface

type PackageTypeEnv = TypeEnv

type PackageIfaceTable = ModuleEnv ModIface

Helps us find information about modules in the imported packages

emptyPackageIfaceTable :: PackageIfaceTable

lookupIfaceByModule :: DynFlags -> HomePackageTable -> PackageIfaceTable -> Module -> Maybe ModIface

Find the ModIface for a Module, searching in both the loaded home and external package module information

emptyModIface :: Module -> ModIface

type PackageInstEnv = InstEnv

type PackageRuleBase = RuleBase

Interactive context

data InteractiveContext

Interactive context, recording information relevant to GHCi

Constructors

InteractiveContext

ic_toplev_scope :: [Module]	The context includes the top-level scope of these modules
ic_exports :: [Module]	The context includes just the exports of these modules
ic_rn_gbl_env :: GlobalRdrEnv	The contexts' cached `GlobalRdrEnv`, built from `ic_toplev_scope` and `ic_exports`
ic_tmp_ids :: [Id]	Names bound during interaction with the user. Later Ids shadow earlier ones with the same OccName.
ic_tyvars :: TyVarSet	Skolem type variables free in `ic_tmp_ids`. These arise at breakpoints in a polymorphic context, where we have only partial type information.
ic_resume :: [Resume]	The stack of breakpoint contexts

emptyInteractiveContext :: InteractiveContext

icPrintUnqual :: DynFlags -> InteractiveContext -> PrintUnqualified

mkPrintUnqualified :: DynFlags -> GlobalRdrEnv -> PrintUnqualified

Creates some functions that work out the best ways to format names for the user according to a set of heuristics

extendInteractiveContext :: InteractiveContext -> [Id] -> TyVarSet -> InteractiveContext

substInteractiveContext :: InteractiveContext -> TvSubst -> InteractiveContext

Interfaces

data ModIface

A ModIface plus a ModDetails summarises everything we know about a compiled module. The ModIface is the stuff *before* linking, and can be written out to an interface file. The 'ModDetails is after linking and can be completely recovered from just the ModIface.

When we read an interface file, we also construct a ModIface from it, except that we explicitly make the mi_decls and a few other fields empty; as when reading we consolidate the declarations etc. into a number of indexed maps and environments in the ExternalPackageState.

Constructors

ModIface

mi_module :: !Module	Name of the module we are for
mi_iface_hash :: !Fingerprint	Hash of the whole interface
mi_mod_hash :: !Fingerprint	Hash of the ABI only
mi_orphan :: !WhetherHasOrphans	Whether this module has orphans
mi_finsts :: !WhetherHasFamInst	Whether this module has family instances
mi_boot :: !IsBootInterface	Read from an hi-boot file?
mi_deps :: Dependencies	The dependencies of the module, consulted for directly imported modules only
mi_usages :: [Usage]	Usages; kept sorted so that it's easy to decide whether to write a new iface file (changing usages doesn't affect the hash of this module)
mi_exports :: ![IfaceExport]	Records the modules that are the declaration points for things exported by this module, and the `OccName`s of those things
mi_exp_hash :: !Fingerprint	Hash of export list
mi_fixities :: [(OccName, Fixity)]	Fixities
mi_warns :: Warnings	Warnings
mi_decls :: [(Fingerprint, IfaceDecl)]	Sorted type, variable, class etc. declarations
mi_globals :: !(Maybe GlobalRdrEnv)	Binds all the things defined at the top level in the original source code for this module. which is NOT the same as mi_exports, nor mi_decls (which may contains declarations for things not actually defined by the user). Used for GHCi and for inspecting the contents of modules via the GHC API only. (We need the source file to figure out the top-level environment, if we didn't compile this module from source then this field contains `Nothing`). Strictly speaking this field should live in the `HomeModInfo`, but that leads to more plumbing.
mi_insts :: [IfaceInst]	Sorted class instance
mi_fam_insts :: [IfaceFamInst]	Sorted family instances
mi_rules :: [IfaceRule]	Sorted rules
mi_orphan_hash :: !Fingerprint	Hash for orphan rules and class and family instances combined
mi_vect_info :: !IfaceVectInfo	Vectorisation information
mi_warn_fn :: Name -> Maybe WarningTxt	Cached lookup for `mi_warns`
mi_fix_fn :: OccName -> Fixity	Cached lookup for `mi_fixities`
mi_hash_fn :: OccName -> Maybe (OccName, Fingerprint)	Cached lookup for `mi_decls`. The `Nothing` in `mi_hash_fn` means that the thing isn't in decls. It's useful to know that when seeing if we are up to date wrt. the old interface. The `OccName` is the parent of the name, if it has one.
mi_hpc :: !AnyHpcUsage	True if this program uses Hpc at any point in the program.

Instances

Binary ModIface

mkIfaceWarnCache :: Warnings -> Name -> Maybe WarningTxt

Constructs the cache for the mi_warn_fn field of a ModIface

mkIfaceHashCache :: [(Fingerprint, IfaceDecl)] -> OccName -> Maybe (OccName, Fingerprint)

Constructs cache for the mi_hash_fn field of a ModIface

mkIfaceFixCache :: [(OccName, Fixity)] -> OccName -> Fixity

Creates cached lookup for the mi_fix_fn field of ModIface

emptyIfaceWarnCache :: Name -> Maybe WarningTxt

Fixity

type FixityEnv = NameEnv FixItem

Fixity environment mapping names to their fixities

data FixItem

Fixity information for an Name. We keep the OccName in the range so that we can generate an interface from it

Constructors

FixItem OccName Fixity

Instances

Outputable FixItem

lookupFixity :: FixityEnv -> Name -> Fixity

emptyFixityEnv :: FixityEnv

TyThings and type environments

data TyThing

A typecheckable-thing, essentially anything that has a name

Constructors

AnId Id
ADataCon DataCon
ATyCon TyCon
AClass Class

Instances

Outputable TyThing

NamedThing TyThing

tyThingClass :: TyThing -> Class

Get the Class from a TyThing if it is a class thing. Panics otherwise

tyThingTyCon :: TyThing -> TyCon

Get the TyCon from a TyThing if it is a type constructor thing. Panics otherwise

tyThingDataCon :: TyThing -> DataCon

Get the DataCon from a TyThing if it is a data constructor thing. Panics otherwise

tyThingId :: TyThing -> Id

Get the Id from a TyThing if it is a id *or* data constructor thing. Panics otherwise

implicitTyThings :: TyThing -> [TyThing]

Determine the TyThings brought into scope by another TyThing other than itself. For example, Id's don't have any implicit TyThings as they just bring themselves into scope, but classes bring their dictionary datatype, type constructor and some selector functions into scope, just for a start!

isImplicitTyThing :: TyThing -> Bool

Returns True if there should be no interface-file declaration for this thing on its own: either it is built-in, or it is part of some other declaration, or it is generated implicitly by some other declaration.

type TypeEnv = NameEnv TyThing

A map from Names to TyThings, constructed by typechecking local declarations or interface files

lookupType :: DynFlags -> HomePackageTable -> PackageTypeEnv -> Name -> Maybe TyThing

Find the TyThing for the given Name by using all the resources at our disposal: the compiled modules in the HomePackageTable and the compiled modules in other packages that live in PackageTypeEnv. Note that this does NOT look up the TyThing in the module being compiled: you have to do that yourself, if desired

lookupTypeHscEnv :: HscEnv -> Name -> IO (Maybe TyThing)

As lookupType, but with a marginally easier-to-use interface if you have a HscEnv

mkTypeEnv :: [TyThing] -> TypeEnv

emptyTypeEnv :: TypeEnv

extendTypeEnv :: TypeEnv -> TyThing -> TypeEnv

extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv

extendTypeEnvWithIds :: TypeEnv -> [Id] -> TypeEnv

lookupTypeEnv :: TypeEnv -> Name -> Maybe TyThing

typeEnvElts :: TypeEnv -> [TyThing]

typeEnvClasses :: TypeEnv -> [Class]

typeEnvTyCons :: TypeEnv -> [TyCon]

typeEnvIds :: TypeEnv -> [Id]

typeEnvDataCons :: TypeEnv -> [DataCon]

MonadThings

class Monad m => MonadThings m where

Class that abstracts out the common ability of the monads in GHC to lookup a TyThing in the monadic environment by Name. Provides a number of related convenience functions for accessing particular kinds of TyThing

Methods

lookupThing :: Name -> m TyThing

lookupId :: Name -> m Id

lookupDataCon :: Name -> m DataCon

lookupTyCon :: Name -> m TyCon

lookupClass :: Name -> m Class

Instances

MonadThings (IOEnv (Env DsGblEnv DsLclEnv))

Information on imports and exports

type WhetherHasOrphans = Bool

Records whether a module has orphans. An "orphan" is one of:

An instance declaration in a module other than the definition module for one of the type constructors or classes in the instance head
A transformation rule in a module other than the one defining the function in the head of the rule

type IsBootInterface = Bool

Did this module originate from a *-boot file?

data Usage

Records modules that we depend on by making a direct import from

Constructors

UsagePackageModule

Module from another package

usg_mod :: Module	External package module depended on
usg_mod_hash :: Fingerprint

UsageHomeModule

Module from the current package

usg_mod_name :: ModuleName	Name of the module
usg_mod_hash :: Fingerprint	Cached module fingerprint
usg_entities :: [(OccName, Fingerprint)]	Entities we depend on, sorted by occurrence name and fingerprinted. NB: usages are for parent names only, e.g. type constructors but not the associated data constructors.
usg_exports :: Maybe Fingerprint	Fingerprint for the export list we used to depend on this module, if we depend on the export list

Instances

Eq Usage

Binary Usage

data Dependencies

Dependency information about modules and packages below this one in the import hierarchy.

Invariant: the dependencies of a module M never includes M.

Invariant: none of the lists contain duplicates.

Constructors

Deps

dep_mods :: [(ModuleName, IsBootInterface)]	Home-package module dependencies
dep_pkgs :: [PackageId]	External package dependencies
dep_orphs :: [Module]	Orphan modules (whether home or external pkg), not including family instance orphans as they are anyway included in `dep_finsts`
dep_finsts :: [Module]	Modules that contain family instances (whether the instances are from the home or an external package)

Instances

Eq Dependencies

Binary Dependencies

noDependencies :: Dependencies

data NameCache

The NameCache makes sure that there is just one Unique assigned for each original name; i.e. (module-name, occ-name) pair and provides something of a lookup mechanism for those names.

Constructors

NameCache

nsUniqs :: UniqSupply	Supply of uniques
nsNames :: OrigNameCache	Ensures that one original name gets one unique
nsIPs :: OrigIParamCache	Ensures that one implicit parameter name gets one unique

type OrigNameCache = ModuleEnv (OccEnv Name)

Per-module cache of original OccNames given Names

type OrigIParamCache = FiniteMap (IPName OccName) (IPName Name)

Module-local cache of implicit parameter OccNames given Names

type Avails = [AvailInfo]

A collection of AvailInfo - several things that are "available"

availsToNameSet :: [AvailInfo] -> NameSet

availsToNameEnv :: [AvailInfo] -> NameEnv AvailInfo

availName :: GenAvailInfo name -> name

Just the main name made available, i.e. not the available pieces of type or class brought into scope by the GenAvailInfo

availNames :: GenAvailInfo name -> [name]

All names made available by the availability information

data GenAvailInfo name

Records what things are available, i.e. in scope

Constructors

Avail name An ordinary identifier in scope

AvailTC name [name]

A type or class in scope. Parameters:

1) The name of the type or class

2) The available pieces of type or class. NB: If the type or class is itself to be in scope, it must be in this list. Thus, typically: AvailTC Eq [Eq, ==, /=]

Instances

Eq name => Eq (GenAvailInfo name)

Outputable n => Outputable (GenAvailInfo n)

Binary name => Binary (GenAvailInfo name)

type AvailInfo = GenAvailInfo Name

Named things that are available

type RdrAvailInfo = GenAvailInfo OccName

RdrNamed things that are available

type IfaceExport = (Module, [GenAvailInfo OccName])

The original names declared of a certain module that are exported

Warnings

data Warnings

Warning information for a module

Constructors

NoWarnings	Nothing deprecated
WarnAll WarningTxt	Whole module deprecated
WarnSome [(OccName, WarningTxt)]	Some specific things deprecated

Instances

Eq Warnings

Outputable Warnings

Binary Warnings

data WarningTxt

Constructors

WarningTxt FastString
DeprecatedTxt FastString

Instances

Eq WarningTxt

Outputable WarningTxt

Binary WarningTxt

plusWarns :: Warnings -> Warnings -> Warnings

Linker stuff

data Linkable

Information we can use to dynamically link modules into the compiler

Constructors

linkableTime :: ClockTime	Time at which this linkable was built (i.e. when the bytecodes were produced, or the mod date on the files)
linkableModule :: Module	The linkable module itself
linkableUnlinked :: [Unlinked]	Those files and chunks of code we have yet to link

Instances

Outputable Linkable

isObjectLinkable :: Linkable -> Bool

data Unlinked

Objects which have yet to be linked by the compiler

Constructors

DotO FilePath	An object file (.o)
DotA FilePath	Static archive file (.a)
DotDLL FilePath	Dynamically linked library file (.so, .dll, .dylib)
BCOs CompiledByteCode ModBreaks	A byte-code object, lives only in memory

Instances

Outputable Unlinked

data CompiledByteCode

Instances

Outputable CompiledByteCode

isObject :: Unlinked -> Bool

Is this an actual file on disk we can link in somehow?

nameOfObject :: Unlinked -> FilePath

Retrieve the filename of the linkable if possible. Panic if it is a byte-code object

isInterpretable :: Unlinked -> Bool

Is this a bytecode linkable with no file on disk?

byteCodeOfObject :: Unlinked -> CompiledByteCode

Retrieve the compiled byte-code if possible. Panic if it is a file-based linkable

Program coverage

data HpcInfo

Information about a modules use of Haskell Program Coverage

Constructors

HpcInfo

hpcInfoTickCount :: Int
hpcInfoHash :: Int

NoHpcInfo

hpcUsed :: AnyHpcUsage

Is hpc used anywhere on the module *tree*?

emptyHpcInfo :: AnyHpcUsage -> HpcInfo

isHpcUsed :: HpcInfo -> AnyHpcUsage

Find out if HPC is used by this module or any of the modules it depends upon

type AnyHpcUsage = Bool

This is used to signal if one of my imports used HPC instrumentation even if there is no module-local HPC usage

Breakpoints

data ModBreaks

All the information about the breakpoints for a given module

Constructors

ModBreaks

modBreaks_flags :: BreakArray	The array of flags, one per breakpoint, indicating which breakpoints are enabled.
modBreaks_locs :: !(Array BreakIndex SrcSpan)	An array giving the source span of each breakpoint.
modBreaks_vars :: !(Array BreakIndex [OccName])	An array giving the names of the free variables at each breakpoint.

type BreakIndex = Int

Breakpoint index

emptyModBreaks :: ModBreaks

Vectorisation information

data VectInfo

Vectorisation information for ModGuts, ModDetails and ExternalPackageState. All of this information is always tidy, even in ModGuts.

Constructors

VectInfo

vectInfoVar :: VarEnv (Var, Var)	`(f, f_v)` keyed on `f`
vectInfoTyCon :: NameEnv (TyCon, TyCon)	`(T, T_v)` keyed on `T`
vectInfoDataCon :: NameEnv (DataCon, DataCon)	`(C, C_v)` keyed on `C`
vectInfoPADFun :: NameEnv (TyCon, Var)	`(T_v, paT)` keyed on `T_v`
vectInfoIso :: NameEnv (TyCon, Var)	`(T, isoT)` keyed on `T`

data IfaceVectInfo

Vectorisation information for ModIface: a slightly less low-level view

Constructors

IfaceVectInfo

ifaceVectInfoVar :: [Name]	All variables in here have a vectorised variant
ifaceVectInfoTyCon :: [Name]	All `TyCon`s in here have a vectorised variant; the name of the vectorised variant and those of its data constructors are determined by OccName.mkVectTyConOcc and OccName.mkVectDataConOcc; the names of the isomorphisms are determined by OccName.mkVectIsoOcc
ifaceVectInfoTyConReuse :: [Name]	The vectorised form of all the `TyCon`s in here coincides with the unconverted form; the name of the isomorphisms is determined by OccName.mkVectIsoOcc

Instances

Binary IfaceVectInfo

noVectInfo :: VectInfo

plusVectInfo :: VectInfo -> VectInfo -> VectInfo

noIfaceVectInfo :: IfaceVectInfo

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