-%
+
% (c) The University of Glasgow, 2000
%
\section[HscTypes]{Types for the per-module compiler}
\begin{code}
module HscTypes (
+ HscEnv(..), hscEPS,
GhciMode(..),
- ModuleLocation(..),
-
- ModDetails(..), ModIface(..),
- HomeSymbolTable, emptySymbolTable,
- PackageTypeEnv,
- HomeIfaceTable, PackageIfaceTable, emptyIfaceTable,
- lookupIface, lookupIfaceByModName,
- emptyModIface,
+ ModDetails(..),
+ ModGuts(..), ModImports(..), ForeignStubs(..),
- InteractiveContext(..),
+ HomePackageTable, HomeModInfo(..), emptyHomePackageTable,
- IfaceDecls, mkIfaceDecls, dcl_tycl, dcl_rules, dcl_insts,
+ ExternalPackageState(..),
+ PackageTypeEnv, PackageIfaceTable, emptyPackageIfaceTable,
+ lookupIface, lookupIfaceByModName, moduleNameToModule,
+ emptyModIface,
- VersionInfo(..), initialVersionInfo, lookupVersion,
+ InteractiveContext(..), emptyInteractiveContext,
+ icPrintUnqual, unQualInScope,
- TyThing(..), isTyClThing, implicitTyThingIds,
+ ModIface(..), mkIfaceDepCache, mkIfaceVerCache, mkIfaceFixCache,
+ emptyIfaceDepCache,
- TypeEnv, lookupType, mkTypeEnv, emptyTypeEnv,
- extendTypeEnvList, extendTypeEnvWithIds,
- typeEnvClasses, typeEnvTyCons, typeEnvIds,
+ Deprecs(..), IfaceDeprecs,
- ImportedModuleInfo, WhetherHasOrphans, ImportVersion, WhatsImported(..),
- PersistentRenamerState(..), IsBootInterface, DeclsMap,
- IfaceInsts, IfaceRules, GatedDecl, GatedDecls, IsExported,
- NameSupply(..), OrigNameCache, OrigIParamCache,
- Avails, AvailEnv, GenAvailInfo(..), AvailInfo, RdrAvailInfo,
- PersistentCompilerState(..),
+ FixityEnv, FixItem(..), lookupFixity, emptyFixityEnv,
- Deprecations(..), lookupDeprec,
+ implicitTyThings, isImplicitTyThing,
- InstEnv, ClsInstEnv, DFunId,
+ TyThing(..), tyThingClass, tyThingTyCon, tyThingDataCon, tyThingId,
+ TypeEnv, lookupType, mkTypeEnv, emptyTypeEnv,
+ extendTypeEnvList, extendTypeEnvWithIds, lookupTypeEnv,
+ typeEnvElts, typeEnvClasses, typeEnvTyCons, typeEnvIds,
+
+ WhetherHasOrphans, IsBootInterface, Usage(..),
+ Dependencies(..), noDependencies,
+ Pool(..), emptyPool, DeclPool, InstPool,
+ Gated,
+ RulePool, addRuleToPool,
+ NameCache(..), OrigNameCache, OrigIParamCache,
+ Avails, availsToNameSet, availName, availNames,
+ GenAvailInfo(..), AvailInfo, RdrAvailInfo,
+ IfaceExport,
+
+ Deprecations, DeprecTxt, lookupDeprec, plusDeprecs,
+
+ InstEnv, DFunId,
PackageInstEnv, PackageRuleBase,
- GlobalRdrEnv, GlobalRdrElt(..), pprGlobalRdrEnv,
- LocalRdrEnv, extendLocalRdrEnv,
-
-
- -- Provenance
- Provenance(..), ImportReason(..),
- pprNameProvenance, hasBetterProv
-
+ -- Linker stuff
+ Linkable(..), isObjectLinkable,
+ Unlinked(..), CompiledByteCode,
+ isObject, nameOfObject, isInterpretable, byteCodeOfObject
) where
#include "HsVersions.h"
-import RdrName ( RdrNameEnv, addListToRdrEnv, emptyRdrEnv, mkRdrUnqual, rdrEnvToList )
-import Name ( Name, NamedThing, getName, nameOccName, nameModule, nameSrcLoc )
+#ifdef GHCI
+import ByteCodeAsm ( CompiledByteCode )
+#endif
+
+import RdrName ( GlobalRdrEnv, emptyGlobalRdrEnv,
+ LocalRdrEnv, emptyLocalRdrEnv,
+ GlobalRdrElt(..), unQualOK )
+import Name ( Name, NamedThing, getName, nameOccName, nameModule )
import NameEnv
-import OccName ( OccName )
-import Module ( Module, ModuleName, ModuleEnv,
- lookupModuleEnv, lookupModuleEnvByName, emptyModuleEnv
- )
-import InstEnv ( InstEnv, ClsInstEnv, DFunId )
+import NameSet
+import OccName ( OccName, OccEnv, lookupOccEnv, mkOccEnv, emptyOccEnv,
+ extendOccEnv, foldOccEnv )
+import Module
+import InstEnv ( InstEnv, DFunId )
import Rules ( RuleBase )
import CoreSyn ( CoreBind )
-import Id ( Id )
-import Class ( Class, classSelIds )
-import TyCon ( TyCon, tyConGenIds, tyConSelIds, tyConDataConsIfAvailable )
-import DataCon ( dataConId, dataConWrapId )
+import Id ( Id, isImplicitId )
+import Type ( TyThing(..) )
-import BasicTypes ( Version, initialVersion, Fixity )
+import Class ( Class, classSelIds, classTyCon )
+import TyCon ( TyCon, isClassTyCon, tyConSelIds, tyConDataCons )
+import DataCon ( dataConImplicitIds )
+import Packages ( PackageName )
+import CmdLineOpts ( DynFlags )
-import HsSyn ( DeprecTxt, tyClDeclName, ifaceRuleDeclName )
-import RdrHsSyn ( RdrNameInstDecl, RdrNameRuleDecl, RdrNameTyClDecl )
-import RnHsSyn ( RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl )
+import BasicTypes ( Version, initialVersion, IPName,
+ Fixity, defaultFixity, DeprecTxt )
-import CoreSyn ( IdCoreRule )
+import IfaceSyn ( IfaceInst, IfaceRule, IfaceDecl(ifName) )
import FiniteMap ( FiniteMap )
-import Bag ( Bag )
-import Maybes ( seqMaybe, orElse )
+import CoreSyn ( IdCoreRule )
+import PrelNames ( isBuiltInSyntaxName )
+import Maybes ( orElse )
import Outputable
-import SrcLoc ( SrcLoc, isGoodSrcLoc )
-import Util ( thenCmp, sortLt )
+import SrcLoc ( SrcLoc )
import UniqSupply ( UniqSupply )
+import Maybe ( fromJust )
+import FastString ( FastString )
+
+import DATA_IOREF ( IORef, readIORef )
+import Time ( ClockTime )
\end{code}
+
%************************************************************************
%* *
-\subsection{Which mode we're in
+\subsection{Compilation environment}
%* *
%************************************************************************
+The HscEnv gives the environment in which to compile a chunk of code.
+
+\begin{code}
+data HscEnv
+ = HscEnv { hsc_mode :: GhciMode,
+ hsc_dflags :: DynFlags,
+
+ hsc_HPT :: HomePackageTable,
+ -- The home package table describes already-compiled
+ -- home-packge 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.)
+ -- hsc_HPT is not mutable because we only demand-load
+ -- external packages; the home package is eagerly
+ -- loaded by the compilation manager.
+
+ -- The next two are side-effected by compiling
+ -- to reflect sucking in interface files
+ hsc_EPS :: IORef ExternalPackageState,
+ hsc_NC :: IORef NameCache }
+
+hscEPS :: HscEnv -> IO ExternalPackageState
+hscEPS hsc_env = readIORef (hsc_EPS hsc_env)
+\end{code}
+
+The GhciMode is self-explanatory:
+
\begin{code}
data GhciMode = Batch | Interactive | OneShot
- deriving Eq
+ deriving Eq
\end{code}
+\begin{code}
+type HomePackageTable = ModuleEnv HomeModInfo -- Domain = modules in the home package
+type PackageIfaceTable = ModuleEnv ModIface -- Domain = modules in the imported packages
+
+emptyHomePackageTable = emptyModuleEnv
+emptyPackageIfaceTable = emptyModuleEnv
+
+data HomeModInfo
+ = HomeModInfo { hm_iface :: ModIface,
+ hm_globals :: Maybe GlobalRdrEnv, -- Its top level environment
+ -- Nothing <-> compiled module
+ hm_details :: ModDetails,
+ hm_linkable :: Linkable }
+\end{code}
-%************************************************************************
-%* *
-\subsection{Module locations}
-%* *
-%************************************************************************
+Simple lookups in the symbol table.
\begin{code}
-data ModuleLocation
- = ModuleLocation {
- ml_hs_file :: Maybe FilePath,
- ml_hspp_file :: Maybe FilePath, -- path of preprocessed source
- ml_hi_file :: FilePath,
- ml_obj_file :: Maybe FilePath
- }
- deriving Show
+lookupIface :: HomePackageTable -> PackageIfaceTable -> Module -> Maybe ModIface
+-- We often have two IfaceTables, and want to do a lookup
+lookupIface hpt pit mod
+ = case lookupModuleEnv hpt mod of
+ Just mod_info -> Just (hm_iface mod_info)
+ Nothing -> lookupModuleEnv pit mod
-instance Outputable ModuleLocation where
- ppr = text . show
+lookupIfaceByModName :: HomePackageTable -> PackageIfaceTable -> ModuleName -> Maybe ModIface
+-- We often have two IfaceTables, and want to do a lookup
+lookupIfaceByModName hpt pit mod
+ = case lookupModuleEnvByName hpt mod of
+ Just mod_info -> Just (hm_iface mod_info)
+ Nothing -> lookupModuleEnvByName pit mod
\end{code}
-For a module in another package, the hs_file and obj_file
-components of ModuleLocation are undefined.
-
-The locations specified by a ModuleLocation may or may not
-correspond to actual files yet: for example, even if the object
-file doesn't exist, the ModuleLocation still contains the path to
-where the object file will reside if/when it is created.
+\begin{code}
+-- Use instead of Finder.findModule if possible: this way doesn't
+-- require filesystem operations, and it is guaranteed not to fail
+-- when the IfaceTables are properly populated (i.e. after the renamer).
+moduleNameToModule :: HomePackageTable -> PackageIfaceTable -> ModuleName -> Module
+moduleNameToModule hpt pit mod
+ = mi_module (fromJust (lookupIfaceByModName hpt pit mod))
+\end{code}
%************************************************************************
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; it is the "linked" form of the mi_decls field.
+and can be written out to an interface file. (The @ModDetails@ is after
+linking; it is the "linked" form of the mi_decls field.)
+
+When we *read* an interface file, we also construct a @ModIface@ from it,
+except that the mi_decls part is empty; when reading we consolidate
+the declarations into a single indexed map in the @PersistentRenamerState@.
\begin{code}
data ModIface
= ModIface {
- mi_module :: Module, -- Complete with package info
- mi_version :: VersionInfo, -- Module version number
- mi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
- mi_boot :: IsBootInterface, -- Whether this interface was read from an hi-boot file
-
- mi_usages :: [ImportVersion Name], -- Usages; kept sorted so that it's easy
- -- to decide whether to write a new iface file
- -- (changing usages doesn't affect the version of
- -- this module)
-
- mi_exports :: [(ModuleName,Avails)], -- What it exports
- -- Kept sorted by (mod,occ),
- -- to make version comparisons easier
-
- mi_globals :: GlobalRdrEnv, -- Its top level environment
-
- mi_fixities :: NameEnv Fixity, -- Fixities
- mi_deprecs :: Deprecations, -- Deprecations
-
- mi_decls :: IfaceDecls -- The RnDecls form of ModDetails
+ mi_package :: !PackageName, -- Which package the module comes from
+ mi_module :: !Module,
+ mi_mod_vers :: !Version, -- Module version: changes when anything changes
+
+ mi_orphan :: !WhetherHasOrphans, -- Whether this module has orphans
+ mi_boot :: !IsBootInterface, -- Read from an hi-boot file?
+
+ mi_deps :: Dependencies,
+ -- This is consulted for directly-imported modules,
+ -- but not for anything else (hence lazy)
+
+ -- Usages; kept sorted so that it's easy to decide
+ -- whether to write a new iface file (changing usages
+ -- doesn't affect the version of this module)
+ mi_usages :: [Usage],
+ -- NOT STRICT! we read this field lazily from the interface file
+ -- It is *only* consulted by the recompilation checker
+
+ -- Exports
+ -- Kept sorted by (mod,occ), to make version comparisons easier
+ mi_exports :: ![IfaceExport],
+ mi_exp_vers :: !Version, -- Version number of export list
+
+ -- Fixities
+ mi_fixities :: [(OccName,Fixity)],
+ -- NOT STRICT! we read this field lazily from the interface file
+
+ -- Deprecations
+ mi_deprecs :: Deprecs [(OccName,DeprecTxt)],
+ -- NOT STRICT! we read this field lazily from the interface file
+
+ -- Type, class and variable declarations
+ -- The version of an Id changes if its fixity or deprecations change
+ -- (as well as its type of course)
+ -- Ditto data constructors, class operations, except that
+ -- the version of the parent class/tycon changes
+ mi_decls :: [(Version,IfaceDecl)], -- Sorted
+
+ -- Instance declarations and rules
+ mi_insts :: [IfaceInst], -- Sorted
+ mi_rules :: [IfaceRule], -- Sorted
+ mi_rule_vers :: !Version, -- Version number for rules and instances combined
+
+ -- Cached environments for easy lookup
+ -- These are computed (lazily) from other fields
+ -- and are not put into the interface file
+ mi_dep_fn :: Name -> Maybe DeprecTxt, -- Cached lookup for mi_deprecs
+ mi_fix_fn :: OccName -> Fixity, -- Cached lookup for mi_fixities
+ mi_ver_fn :: OccName -> Maybe Version -- Cached lookup for mi_decls
+ -- The Nothing in mi_ver_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
}
-data IfaceDecls = IfaceDecls { dcl_tycl :: [RenamedTyClDecl], -- Sorted
- dcl_rules :: [RenamedRuleDecl], -- Sorted
- dcl_insts :: [RenamedInstDecl] } -- Unsorted
-
-mkIfaceDecls :: [RenamedTyClDecl] -> [RenamedRuleDecl] -> [RenamedInstDecl] -> IfaceDecls
-mkIfaceDecls tycls rules insts
- = IfaceDecls { dcl_tycl = sortLt lt_tycl tycls,
- dcl_rules = sortLt lt_rule rules,
- dcl_insts = insts }
- where
- d1 `lt_tycl` d2 = tyClDeclName d1 < tyClDeclName d2
- r1 `lt_rule` r2 = ifaceRuleDeclName r1 < ifaceRuleDeclName r2
-
-
--- typechecker should only look at this, not ModIface
-- Should be able to construct ModDetails from mi_decls in ModIface
data ModDetails
= ModDetails {
-- The next three fields are created by the typechecker
- md_types :: TypeEnv,
- md_insts :: [DFunId], -- Dfun-ids for the instances in this module
- md_rules :: [IdCoreRule], -- Domain may include Ids from other modules
- md_binds :: [CoreBind]
+ md_types :: !TypeEnv,
+ md_insts :: ![DFunId], -- Dfun-ids for the instances in this module
+ md_rules :: ![IdCoreRule] -- Domain may include Ids from other modules
}
--- The ModDetails takes on several slightly different forms:
---
--- After typecheck + desugar
--- md_types Contains TyCons, Classes, and hasNoBinding Ids
--- md_insts All instances from this module (incl derived ones)
--- md_rules All rules from this module
--- md_binds Desugared bindings
+-- 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.
+
+data ModGuts
+ = ModGuts {
+ mg_module :: !Module,
+ mg_exports :: !Avails, -- What it exports
+ mg_deps :: !Dependencies, -- What is below it, directly or otherwise
+ mg_dir_imps :: ![Module], -- Directly-imported modules; used to
+ -- generate initialisation code
+ mg_usages :: ![Usage], -- Version info for what it needed
+
+ mg_rdr_env :: !GlobalRdrEnv, -- Top-level lexical environment
+ mg_fix_env :: !FixityEnv, -- Fixity env, for things declared in this module
+ mg_deprecs :: !Deprecations, -- Deprecations declared in the module
+
+ mg_types :: !TypeEnv,
+ mg_insts :: ![DFunId], -- Instances
+ mg_rules :: ![IdCoreRule], -- Rules from this module
+ mg_binds :: ![CoreBind], -- Bindings for this module
+ mg_foreign :: !ForeignStubs
+ }
+
+-- The ModGuts takes on several slightly different forms:
--
--- After simplification
--- md_types Same as after typecheck
--- md_insts Ditto
--- md_rules Orphan rules only (local ones now attached to binds)
--- md_binds With rules attached
+-- After simplification, the following fields change slightly:
+-- mg_rules Orphan rules only (local ones now attached to binds)
+-- mg_binds With rules attached
--
--- After CoreTidy
--- md_types Now contains Ids as well, replete with final IdInfo
+-- After CoreTidy, the following fields change slightly:
+-- mg_types Now contains Ids as well, replete with final IdInfo
-- The Ids are only the ones that are visible from
-- importing modules. Without -O that means only
-- exported Ids, but with -O importing modules may
-- see ids mentioned in unfoldings of exported Ids
--
--- md_insts Same DFunIds as before, but with final IdInfo,
+-- mg_insts Same DFunIds as before, but with final IdInfo,
-- and the unique might have changed; remember that
-- CoreTidy links up the uniques of old and new versions
--
--- md_rules All rules for exported things, substituted with final Ids
---
--- md_binds Tidied
+-- mg_rules All rules for exported things, substituted with final Ids
--
--- Passed back to compilation manager
--- Just as after CoreTidy, but with md_binds nuked
+-- mg_binds Tidied
+
+
+
+data ModImports
+ = ModImports {
+ imp_direct :: ![(Module,Bool)], -- Explicitly-imported modules
+ -- Boolean is true if we imported the whole
+ -- module (apart, perhaps, from hiding some)
+ imp_pkg_mods :: !ModuleSet, -- Non-home-package modules on which we depend,
+ -- directly or indirectly
+ imp_home_names :: !NameSet -- Home package things on which we depend,
+ -- directly or indirectly
+ }
+
+data ForeignStubs = NoStubs
+ | ForeignStubs
+ SDoc -- Header file prototypes for
+ -- "foreign exported" functions
+ SDoc -- C stubs to use when calling
+ -- "foreign exported" functions
+ [FastString] -- Headers that need to be included
+ -- into C code generated for this module
+ [Id] -- Foreign-exported binders
+ -- we have to generate code to register these
\end{code}
\begin{code}
-emptyModIface :: Module -> ModIface
-emptyModIface mod
- = ModIface { mi_module = mod,
- mi_version = initialVersionInfo,
- mi_usages = [],
+emptyModIface :: PackageName -> ModuleName -> ModIface
+emptyModIface pkg mod
+ = ModIface { mi_package = pkg,
+ mi_module = mkModule pkg mod,
+ mi_mod_vers = initialVersion,
mi_orphan = False,
mi_boot = False,
+ mi_deps = noDependencies,
+ mi_usages = [],
mi_exports = [],
- mi_fixities = emptyNameEnv,
- mi_globals = emptyRdrEnv,
+ mi_exp_vers = initialVersion,
+ mi_fixities = [],
mi_deprecs = NoDeprecs,
- mi_decls = panic "emptyModIface: decls"
+ mi_insts = [],
+ mi_rules = [],
+ mi_decls = [],
+ mi_rule_vers = initialVersion,
+ mi_dep_fn = emptyIfaceDepCache,
+ mi_fix_fn = emptyIfaceFixCache,
+ mi_ver_fn = emptyIfaceVerCache
}
\end{code}
-Symbol tables map modules to ModDetails:
+
+%************************************************************************
+%* *
+\subsection{The interactive context}
+%* *
+%************************************************************************
\begin{code}
-type SymbolTable = ModuleEnv ModDetails
-type IfaceTable = ModuleEnv ModIface
+data InteractiveContext
+ = InteractiveContext {
+ ic_toplev_scope :: [String], -- Include the "top-level" scope of
+ -- these modules
+
+ ic_exports :: [String], -- Include just the exports of these
+ -- modules
+
+ ic_rn_gbl_env :: GlobalRdrEnv, -- The cached GlobalRdrEnv, built from
+ -- ic_toplev_scope and ic_exports
-type HomeIfaceTable = IfaceTable
-type PackageIfaceTable = IfaceTable
+ ic_rn_local_env :: LocalRdrEnv, -- Lexical context for variables bound
+ -- during interaction
-type HomeSymbolTable = SymbolTable -- Domain = modules in the home package
+ ic_type_env :: TypeEnv -- Ditto for types
+ }
-emptySymbolTable :: SymbolTable
-emptySymbolTable = emptyModuleEnv
+emptyInteractiveContext
+ = InteractiveContext { ic_toplev_scope = [],
+ ic_exports = [],
+ ic_rn_gbl_env = emptyGlobalRdrEnv,
+ ic_rn_local_env = emptyLocalRdrEnv,
+ ic_type_env = emptyTypeEnv }
-emptyIfaceTable :: IfaceTable
-emptyIfaceTable = emptyModuleEnv
+icPrintUnqual :: InteractiveContext -> PrintUnqualified
+icPrintUnqual ictxt = unQualInScope (ic_rn_gbl_env ictxt)
\end{code}
-Simple lookups in the symbol table.
+@unQualInScope@ returns a function that takes a @Name@ and tells whether
+its unqualified name is in scope. This is put as a boolean flag in
+the @Name@'s provenance to guide whether or not to print the name qualified
+in error messages.
\begin{code}
-lookupIface :: HomeIfaceTable -> PackageIfaceTable -> Name -> Maybe ModIface
--- We often have two IfaceTables, and want to do a lookup
-lookupIface hit pit name
- = lookupModuleEnv hit mod `seqMaybe` lookupModuleEnv pit mod
+unQualInScope :: GlobalRdrEnv -> Name -> Bool
+-- True if 'f' is in scope, and has only one binding,
+-- and the thing it is bound to is the name we are looking for
+-- (i.e. false if A.f and B.f are both in scope as unqualified 'f')
+--
+-- Also checks for built-in syntax, which is always 'in scope'
+--
+-- This fn is only efficient if the shared
+-- partial application is used a lot.
+unQualInScope env
+ = \n -> n `elemNameSet` unqual_names || isBuiltInSyntaxName n
where
- mod = nameModule name
-
-lookupIfaceByModName :: HomeIfaceTable -> PackageIfaceTable -> ModuleName -> Maybe ModIface
--- We often have two IfaceTables, and want to do a lookup
-lookupIfaceByModName hit pit mod
- = lookupModuleEnvByName hit mod `seqMaybe` lookupModuleEnvByName pit mod
+ unqual_names :: NameSet
+ unqual_names = foldOccEnv add emptyNameSet env
+ add [gre] unquals | unQualOK gre = addOneToNameSet unquals (gre_name gre)
+ add _ unquals = unquals
\end{code}
%************************************************************************
%* *
-\subsection{The interactive context}
+ TyThing
%* *
%************************************************************************
\begin{code}
-data InteractiveContext
- = InteractiveContext {
- ic_module :: Module, -- The current module in which
- -- the user is sitting
+isImplicitTyThing :: TyThing -> Bool
+isImplicitTyThing (ADataCon dc) = True
+isImplicitTyThing (AnId id) = isImplicitId id
+isImplicitTyThing (ATyCon tc) = isClassTyCon tc
+isImplicitTyThing other = False
+
+implicitTyThings :: TyThing -> [TyThing]
+implicitTyThings (AnId id) = []
+
+ -- For type constructors, add the data cons (and their extras),
+ -- and the selectors and generic-programming Ids too
+ --
+ -- Newtypes don't have a worker Id, so don't generate that?
+implicitTyThings (ATyCon tc) = map AnId (tyConSelIds tc) ++
+ concatMap (extras_plus . ADataCon) (tyConDataCons tc)
+
+ -- For classes, add the class TyCon too (and its extras)
+ -- and the class selector Ids
+implicitTyThings (AClass cl) = map AnId (classSelIds cl) ++
+ extras_plus (ATyCon (classTyCon cl))
+
+
+ -- For data cons add the worker and wrapper (if any)
+implicitTyThings (ADataCon dc) = map AnId (dataConImplicitIds dc)
+
+extras_plus thing = thing : implicitTyThings thing
- ic_rn_env :: LocalRdrEnv, -- Lexical context for variables bound
- -- during interaction
-
- ic_type_env :: TypeEnv -- Ditto for types
- }
+extendTypeEnvWithIds :: TypeEnv -> [Id] -> TypeEnv
+extendTypeEnvWithIds env ids
+ = extendNameEnvList env [(getName id, AnId id) | id <- ids]
\end{code}
-
%************************************************************************
%* *
-\subsection{Type environment stuff}
+ TypeEnv
%* *
%************************************************************************
\begin{code}
-data TyThing = AnId Id
- | ATyCon TyCon
- | AClass Class
-
-isTyClThing :: TyThing -> Bool
-isTyClThing (ATyCon _) = True
-isTyClThing (AClass _) = True
-isTyClThing (AnId _) = False
-
-instance NamedThing TyThing where
- getName (AnId id) = getName id
- getName (ATyCon tc) = getName tc
- getName (AClass cl) = getName cl
-
-instance Outputable TyThing where
- ppr (AnId id) = ptext SLIT("AnId") <+> ppr id
- ppr (ATyCon tc) = ptext SLIT("ATyCon") <+> ppr tc
- ppr (AClass cl) = ptext SLIT("AClass") <+> ppr cl
-
-typeEnvClasses env = [cl | AClass cl <- nameEnvElts env]
-typeEnvTyCons env = [tc | ATyCon tc <- nameEnvElts env]
-typeEnvIds env = [id | AnId id <- nameEnvElts env]
-
-implicitTyThingIds :: [TyThing] -> [Id]
--- Add the implicit data cons and selectors etc
-implicitTyThingIds things
- = concat (map go things)
- where
- go (AnId f) = []
- go (AClass cl) = classSelIds cl
- go (ATyCon tc) = tyConGenIds tc ++
- tyConSelIds tc ++
- [ n | dc <- tyConDataConsIfAvailable tc,
- n <- [dataConId dc, dataConWrapId dc] ]
- -- Synonyms return empty list of constructors and selectors
-\end{code}
-
-
-\begin{code}
type TypeEnv = NameEnv TyThing
-emptyTypeEnv = emptyNameEnv
+emptyTypeEnv :: TypeEnv
+typeEnvElts :: TypeEnv -> [TyThing]
+typeEnvClasses :: TypeEnv -> [Class]
+typeEnvTyCons :: TypeEnv -> [TyCon]
+typeEnvIds :: TypeEnv -> [Id]
+lookupTypeEnv :: TypeEnv -> Name -> Maybe TyThing
+
+emptyTypeEnv = emptyNameEnv
+typeEnvElts env = nameEnvElts env
+typeEnvClasses env = [cl | AClass cl <- typeEnvElts env]
+typeEnvTyCons env = [tc | ATyCon tc <- typeEnvElts env]
+typeEnvIds env = [id | AnId id <- typeEnvElts env]
mkTypeEnv :: [TyThing] -> TypeEnv
mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
+lookupTypeEnv = lookupNameEnv
+
extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
+-- Extend the type environment
extendTypeEnvList env things
- = extendNameEnvList env [(getName thing, thing) | thing <- things]
-
-extendTypeEnvWithIds :: TypeEnv -> [Id] -> TypeEnv
-extendTypeEnvWithIds env ids
- = extendNameEnvList env [(getName id, AnId id) | id <- ids]
+ = foldl extend env things
+ where
+ extend env thing = extendNameEnv env (getName thing) thing
\end{code}
\begin{code}
-lookupType :: HomeSymbolTable -> PackageTypeEnv -> Name -> Maybe TyThing
-lookupType hst pte name
- = case lookupModuleEnv hst (nameModule name) of
- Just details -> lookupNameEnv (md_types details) name
+lookupType :: HomePackageTable -> PackageTypeEnv -> Name -> Maybe TyThing
+lookupType hpt pte name
+ = case lookupModuleEnv hpt (nameModule name) of
+ Just details -> lookupNameEnv (md_types (hm_details details)) name
Nothing -> lookupNameEnv pte name
\end{code}
+
+\begin{code}
+tyThingTyCon (ATyCon tc) = tc
+tyThingTyCon other = pprPanic "tyThingTyCon" (ppr other)
+
+tyThingClass (AClass cls) = cls
+tyThingClass other = pprPanic "tyThingClass" (ppr other)
+
+tyThingDataCon (ADataCon dc) = dc
+tyThingDataCon other = pprPanic "tyThingDataCon" (ppr other)
+
+tyThingId (AnId id) = id
+tyThingId other = pprPanic "tyThingId" (ppr other)
+\end{code}
+
%************************************************************************
%* *
\subsection{Auxiliary types}
but they are mostly elaborated elsewhere
\begin{code}
-data VersionInfo
- = VersionInfo {
- vers_module :: Version, -- Changes when anything changes
- vers_exports :: Version, -- Changes when export list changes
- vers_rules :: Version, -- Changes when any rule changes
- vers_decls :: NameEnv Version
- -- Versions for "big" names only (not data constructors, class ops)
- -- The version of an Id changes if its fixity changes
- -- Ditto data constructors, class operations, except that the version of
- -- the parent class/tycon changes
- --
- -- If a name isn't in the map, it means 'initialVersion'
- }
+mkIfaceVerCache :: [(Version,IfaceDecl)] -> OccName -> Maybe Version
+mkIfaceVerCache pairs
+ = \occ -> lookupOccEnv env occ
+ where
+ env = foldl add emptyOccEnv pairs
+ add env (v,d) = extendOccEnv env (ifName d) v
-initialVersionInfo :: VersionInfo
-initialVersionInfo = VersionInfo { vers_module = initialVersion,
- vers_exports = initialVersion,
- vers_rules = initialVersion,
- vers_decls = emptyNameEnv
- }
+emptyIfaceVerCache :: OccName -> Maybe Version
+emptyIfaceVerCache occ = Nothing
-lookupVersion :: NameEnv Version -> Name -> Version
-lookupVersion env name = lookupNameEnv env name `orElse` initialVersion
+------------------ Deprecations -------------------------
+data Deprecs a
+ = NoDeprecs
+ | DeprecAll DeprecTxt -- Whole module deprecated
+ | DeprecSome a -- Some specific things deprecated
+ deriving( Eq )
-data Deprecations = NoDeprecs
- | DeprecAll DeprecTxt -- Whole module deprecated
- | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
- -- Just "big" names
- -- We keep the Name in the range, so we can print them out
+type IfaceDeprecs = Deprecs [(OccName,DeprecTxt)]
+type Deprecations = Deprecs (NameEnv (OccName,DeprecTxt))
+
+mkIfaceDepCache:: IfaceDeprecs -> Name -> Maybe DeprecTxt
+mkIfaceDepCache NoDeprecs = \n -> Nothing
+mkIfaceDepCache (DeprecAll t) = \n -> Just t
+mkIfaceDepCache (DeprecSome pairs) = lookupOccEnv (mkOccEnv pairs) . nameOccName
+
+emptyIfaceDepCache :: Name -> Maybe DeprecTxt
+emptyIfaceDepCache n = Nothing
lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
lookupDeprec NoDeprecs name = Nothing
Just (_, txt) -> Just txt
Nothing -> Nothing
-instance Eq Deprecations where
- -- Used when checking whether we need write a new interface
- NoDeprecs == NoDeprecs = True
- (DeprecAll t1) == (DeprecAll t2) = t1 == t2
- (DeprecSome e1) == (DeprecSome e2) = nameEnvElts e1 == nameEnvElts e2
- d1 == d2 = False
+plusDeprecs :: Deprecations -> Deprecations -> Deprecations
+plusDeprecs d NoDeprecs = d
+plusDeprecs NoDeprecs d = d
+plusDeprecs d (DeprecAll t) = DeprecAll t
+plusDeprecs (DeprecAll t) d = DeprecAll t
+plusDeprecs (DeprecSome v1) (DeprecSome v2) = DeprecSome (v1 `plusNameEnv` v2)
\end{code}
deriving( Eq )
-- Equality used when deciding if the interface has changed
-type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
-
+type IfaceExport = (ModuleName, [GenAvailInfo OccName])
+
+availsToNameSet :: [AvailInfo] -> NameSet
+availsToNameSet avails = foldl add emptyNameSet avails
+ where
+ add set avail = addListToNameSet set (availNames avail)
+
+availName :: GenAvailInfo name -> name
+availName (Avail n) = n
+availName (AvailTC n _) = n
+
+availNames :: GenAvailInfo name -> [name]
+availNames (Avail n) = [n]
+availNames (AvailTC n ns) = ns
+
instance Outputable n => Outputable (GenAvailInfo n) where
ppr = pprAvail
pprAvail (Avail n) = ppr n
\end{code}
+\begin{code}
+mkIfaceFixCache :: [(OccName, Fixity)] -> OccName -> Fixity
+mkIfaceFixCache pairs
+ = \n -> lookupOccEnv env n `orElse` defaultFixity
+ where
+ env = mkOccEnv pairs
+
+emptyIfaceFixCache :: OccName -> Fixity
+emptyIfaceFixCache n = defaultFixity
+
+-- This fixity environment is for source code only
+type FixityEnv = NameEnv FixItem
+
+-- We keep the OccName in the range so that we can generate an interface from it
+data FixItem = FixItem OccName Fixity SrcLoc
+
+instance Outputable FixItem where
+ ppr (FixItem occ fix loc) = ppr fix <+> ppr occ <+> parens (ppr loc)
+
+emptyFixityEnv :: FixityEnv
+emptyFixityEnv = emptyNameEnv
+
+lookupFixity :: FixityEnv -> Name -> Fixity
+lookupFixity env n = case lookupNameEnv env n of
+ Just (FixItem _ fix _) -> fix
+ Nothing -> defaultFixity
+\end{code}
+
%************************************************************************
%* *
-\subsection{ModIface}
+\subsection{WhatsImported}
%* *
%************************************************************************
-- * a transformation rule in a module other than the one defining
-- the function in the head of the rule.
-type IsBootInterface = Bool
-
-type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
-
-data WhatsImported name = NothingAtAll -- The module is below us in the
- -- hierarchy, but we import nothing
-
- | Everything Version -- Used for modules from other packages;
- -- we record only the module's version number
-
- | Specifically
- Version -- Module version
- (Maybe Version) -- Export-list version, if we depend on it
- [(name,Version)] -- List guaranteed non-empty
- Version -- Rules version
+type IsBootInterface = Bool
- deriving( Eq )
- -- 'Specifically' doesn't let you say "I imported f but none of the rules in
+-- Dependency info about modules and packages below this one
+-- in the import hierarchy. See TcRnTypes.ImportAvails for details.
+--
+-- Invariant: the dependencies of a module M never includes M
+data Dependencies
+ = Deps { dep_mods :: [(ModuleName,IsBootInterface)], -- Home-package module dependencies
+ dep_pkgs :: [PackageName], -- External package dependencies
+ dep_orphs :: [ModuleName] } -- Orphan modules (whether home or external pkg)
+
+noDependencies :: Dependencies
+noDependencies = Deps [] [] []
+
+data Usage
+ = Usage { usg_name :: ModuleName, -- Name of the module
+ usg_mod :: Version, -- Module version
+ usg_entities :: [(OccName,Version)], -- Sorted by occurrence name
+ usg_exports :: Maybe Version, -- Export-list version, if we depend on it
+ usg_rules :: Version -- Orphan-rules version (for non-orphan
+ -- modules this will always be initialVersion)
+ } deriving( Eq )
+ -- This type doesn't let you say "I imported f but none of the rules in
-- the module". If you use anything in the module you get its rule version
-- So if the rules change, you'll recompile, even if you don't use them.
-- This is easy to implement, and it's safer: you might not have used the rules last
-- time round, but if someone has added a new rule you might need it this time
-- The export list field is (Just v) if we depend on the export list:
- -- we imported the module without saying exactly what we imported
+ -- i.e. we imported the module without saying exactly what we imported
-- We need to recompile if the module exports changes, because we might
-- now have a name clash in the importing module.
-
-type IsExported = Name -> Bool -- True for names that are exported from this module
\end{code}
%************************************************************************
%* *
-\subsection{The persistent compiler state}
+ The External Package State
%* *
%************************************************************************
\begin{code}
-data PersistentCompilerState
- = PCS {
- pcs_PIT :: PackageIfaceTable, -- Domain = non-home-package modules
- -- the mi_decls component is empty
-
- pcs_PTE :: PackageTypeEnv, -- Domain = non-home-package modules
- -- except that the InstEnv components is empty
-
- pcs_insts :: PackageInstEnv, -- The total InstEnv accumulated from all
- -- the non-home-package modules
-
- pcs_rules :: PackageRuleBase, -- Ditto RuleEnv
-
- pcs_PRS :: PersistentRenamerState
- }
-\end{code}
-
-The @PersistentRenamerState@ persists across successive calls to the
-compiler.
-
-It contains:
- * A name supply, which deals with allocating unique names to
- (Module,OccName) original names,
-
- * An accumulated TypeEnv from all the modules in imported packages
-
- * An accumulated InstEnv from all the modules in imported packages
- The point is that we don't want to keep recreating it whenever
- we compile a new module. The InstEnv component of pcPST is empty.
- (This means we might "see" instances that we shouldn't "really" see;
- but the Haskell Report is vague on what is meant to be visible,
- so we just take the easy road here.)
-
- * Ditto for rules
-
- * A "holding pen" for declarations that have been read out of
- interface files but not yet sucked in, renamed, and typechecked
-
-\begin{code}
type PackageTypeEnv = TypeEnv
type PackageRuleBase = RuleBase
type PackageInstEnv = InstEnv
-data PersistentRenamerState
- = PRS { prsOrig :: NameSupply,
- prsImpMods :: ImportedModuleInfo,
- prsDecls :: DeclsMap,
- prsInsts :: IfaceInsts,
- prsRules :: IfaceRules
- }
+data ExternalPackageState
+ = EPS {
+ eps_PIT :: !PackageIfaceTable,
+ -- The ModuleIFaces for modules in external packages
+ -- whose interfaces we have opened
+ -- The declarations in these interface files are held in
+ -- eps_decls, eps_insts, eps_rules (below), not in the
+ -- mi_decls fields of the iPIT.
+ -- What _is_ in the iPIT is:
+ -- * The Module
+ -- * Version info
+ -- * Its exports
+ -- * Fixities
+ -- * Deprecations
+
+ eps_PTE :: !PackageTypeEnv, -- Domain = external-package modules
+
+ eps_inst_env :: !PackageInstEnv, -- The total InstEnv accumulated from
+ -- all the external-package modules
+ eps_rule_base :: !PackageRuleBase, -- Ditto RuleEnv
+
+
+ -- Holding pens for stuff that has been read in from file,
+ -- but not yet slurped into the renamer
+ eps_decls :: !DeclPool,
+ -- A single, global map of Names to unslurped decls
+ -- Decls move from here to eps_PTE
+
+ eps_insts :: !InstPool,
+ -- The as-yet un-slurped instance decls
+ -- Decls move from here to eps_inst_env
+ -- Each instance is 'gated' by the names that must be
+ -- available before this instance decl is needed.
+
+ eps_rules :: !RulePool
+ -- Rules move from here to eps_rule_base when
+ -- all their LHS free vars are in the eps_PTE
+ -- To maintain this invariant, we need to check the pool
+ -- a) when adding to the rule pool by loading an interface
+ -- (some of the new rules may alrady have all their
+ -- gates in the eps_PTE)
+ -- b) when extending the eps_PTE when we load a decl
+ -- from the eps_decls pool
+ }
\end{code}
-The NameSupply makes sure that there is just one Unique assigned for
+The NameCache makes sure that there is just one Unique assigned for
each original name; i.e. (module-name, occ-name) pair. The Name is
always stored as a Global, and has the SrcLoc of its binding location.
Actually that's not quite right. When we first encounter the original
we just store junk. Then when we find the binding site, we fix it up.
\begin{code}
-data NameSupply
- = NameSupply { nsUniqs :: UniqSupply,
+data NameCache
+ = NameCache { nsUniqs :: UniqSupply,
-- Supply of uniques
nsNames :: OrigNameCache,
-- Ensures that one original name gets one unique
-- Ensures that one implicit parameter name gets one unique
}
-type OrigNameCache = FiniteMap (ModuleName,OccName) Name
-type OrigIParamCache = FiniteMap OccName Name
-\end{code}
-
-@ImportedModuleInfo@ contains info ONLY about modules that have not yet
-been loaded into the iPIT. These modules are mentioned in interfaces we've
-already read, so we know a tiny bit about them, but we havn't yet looked
-at the interface file for the module itself. It needs to persist across
-invocations of the renamer, at least from Rename.checkOldIface to Rename.renameSource.
-And there's no harm in it persisting across multiple compilations.
-
-\begin{code}
-type ImportedModuleInfo = FiniteMap ModuleName (WhetherHasOrphans, IsBootInterface)
+type OrigNameCache = ModuleEnv (OccEnv Name)
+type OrigIParamCache = FiniteMap (IPName OccName) (IPName Name)
\end{code}
-A DeclsMap contains a binding for each Name in the declaration
-including the constructors of a type decl etc. The Bool is True just
-for the 'main' Name.
-
\begin{code}
-type DeclsMap = (NameEnv (AvailInfo, Bool, (Module, RdrNameTyClDecl)), Int)
- -- The Int says how many have been sucked in
-
-type IfaceInsts = GatedDecls RdrNameInstDecl
-type IfaceRules = GatedDecls RdrNameRuleDecl
-
-type GatedDecls d = (Bag (GatedDecl d), Int) -- The Int says how many have been sucked in
-type GatedDecl d = ([Name], (Module, d))
+data Pool p = Pool (NameEnv p) -- The pool itself, indexed by some primary key
+ Int -- Number of decls slurped into the map
+ Int -- Number of decls slurped out of the map
+
+emptyPool = Pool emptyNameEnv 0 0
+
+instance Outputable p => Outputable (Pool p) where
+ ppr (Pool p n_in n_out) -- Debug printing only
+ = vcat [ptext SLIT("Pool") <+> int n_in <+> int n_out,
+ nest 2 (ppr p)]
+
+type DeclPool = Pool IfaceDecl
+
+-------------------------
+type Gated d = ([Name], (ModuleName, d)) -- The [Name] 'gate' the declaration
+ -- ModuleName records which iface file this
+ -- decl came from
+
+type RulePool = Pool [Gated IfaceRule]
+
+addRuleToPool :: NameEnv [Gated IfaceRule]
+ -> (ModuleName, IfaceRule)
+ -> [Name] -- Free vars of rule; always non-empty
+ -> NameEnv [Gated IfaceRule]
+addRuleToPool rules rule (fv:fvs) = extendNameEnv_C combine rules fv [(fvs,rule)]
+ where
+ combine old _ = (fvs,rule) : old
+
+-------------------------
+type InstPool = Pool [Gated IfaceInst]
+ -- The key of the Pool is the Class
+ -- The Names are the TyCons in the instance head
+ -- For example, suppose this is in an interface file
+ -- instance C T where ...
+ -- We want to slurp this decl if both C and T are "visible" in
+ -- the importing module. See "The gating story" in RnIfaces for details.
\end{code}
%************************************************************************
%* *
-\subsection{Provenance and export info}
+\subsection{Linkable stuff}
%* *
%************************************************************************
-A LocalRdrEnv is used for local bindings (let, where, lambda, case)
-
-\begin{code}
-type LocalRdrEnv = RdrNameEnv Name
-
-extendLocalRdrEnv :: LocalRdrEnv -> [Name] -> LocalRdrEnv
-extendLocalRdrEnv env names
- = addListToRdrEnv env [(mkRdrUnqual (nameOccName n), n) | n <- names]
-\end{code}
-
-The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
-one for each module, corresponding to that module's top-level scope.
+This stuff is in here, rather than (say) in Linker.lhs, because the Linker.lhs
+stuff is the *dynamic* linker, and isn't present in a stage-1 compiler
\begin{code}
-type GlobalRdrEnv = RdrNameEnv [GlobalRdrElt]
- -- The list is because there may be name clashes
- -- These only get reported on lookup, not on construction
-
-data GlobalRdrElt = GRE Name Provenance (Maybe DeprecTxt)
- -- The Maybe DeprecTxt tells whether this name is deprecated
-
-pprGlobalRdrEnv env
- = vcat (map pp (rdrEnvToList env))
- where
- pp (rn, nps) = ppr rn <> colon <+>
- vcat [ppr n <+> pprNameProvenance n p | (GRE n p _) <- nps]
+data Linkable = LM {
+ linkableTime :: ClockTime, -- Time at which this linkable was built
+ -- (i.e. when the bytecodes were produced,
+ -- or the mod date on the files)
+ linkableModName :: ModuleName, -- Should be Module, but see below
+ linkableUnlinked :: [Unlinked]
+ }
+
+isObjectLinkable :: Linkable -> Bool
+isObjectLinkable l = all isObject (linkableUnlinked l)
+
+instance Outputable Linkable where
+ ppr (LM when_made mod unlinkeds)
+ = (text "LinkableM" <+> parens (text (show when_made)) <+> ppr mod)
+ $$ nest 3 (ppr unlinkeds)
+
+-------------------------------------------
+data Unlinked
+ = DotO FilePath
+ | DotA FilePath
+ | DotDLL FilePath
+ | BCOs CompiledByteCode
+
+#ifndef GHCI
+data CompiledByteCode = NoByteCode
+#endif
+
+instance Outputable Unlinked where
+ ppr (DotO path) = text "DotO" <+> text path
+ ppr (DotA path) = text "DotA" <+> text path
+ ppr (DotDLL path) = text "DotDLL" <+> text path
+#ifdef GHCI
+ ppr (BCOs bcos) = text "BCOs" <+> ppr bcos
+#else
+ ppr (BCOs bcos) = text "No byte code"
+#endif
+
+isObject (DotO _) = True
+isObject (DotA _) = True
+isObject (DotDLL _) = True
+isObject _ = False
+
+isInterpretable = not . isObject
+
+nameOfObject (DotO fn) = fn
+nameOfObject (DotA fn) = fn
+nameOfObject (DotDLL fn) = fn
+
+byteCodeOfObject (BCOs bc) = bc
\end{code}
-The "provenance" of something says how it came to be in scope.
-\begin{code}
-data Provenance
- = LocalDef -- Defined locally
-
- | NonLocalDef -- Defined non-locally
- ImportReason
-
--- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
-instance Eq Provenance where
- p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
-
-instance Eq ImportReason where
- p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
-
-instance Ord Provenance where
- compare LocalDef LocalDef = EQ
- compare LocalDef (NonLocalDef _) = LT
- compare (NonLocalDef _) LocalDef = GT
-
- compare (NonLocalDef reason1) (NonLocalDef reason2)
- = compare reason1 reason2
-
-instance Ord ImportReason where
- compare ImplicitImport ImplicitImport = EQ
- compare ImplicitImport (UserImport _ _ _) = LT
- compare (UserImport _ _ _) ImplicitImport = GT
- compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
- = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
-
-
-data ImportReason
- = UserImport Module SrcLoc Bool -- Imported from module M on line L
- -- Note the M may well not be the defining module
- -- for this thing!
- -- The Bool is true iff the thing was named *explicitly* in the import spec,
- -- rather than being imported as part of a group; e.g.
- -- import B
- -- import C( T(..) )
- -- Here, everything imported by B, and the constructors of T
- -- are not named explicitly; only T is named explicitly.
- -- This info is used when warning of unused names.
-
- | ImplicitImport -- Imported implicitly for some other reason
-\end{code}
-\begin{code}
-hasBetterProv :: Provenance -> Provenance -> Bool
--- Choose
--- a local thing over an imported thing
--- a user-imported thing over a non-user-imported thing
--- an explicitly-imported thing over an implicitly imported thing
-hasBetterProv LocalDef _ = True
-hasBetterProv (NonLocalDef (UserImport _ _ _ )) (NonLocalDef ImplicitImport) = True
-hasBetterProv _ _ = False
-
-pprNameProvenance :: Name -> Provenance -> SDoc
-pprNameProvenance name LocalDef = ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
-pprNameProvenance name (NonLocalDef why) = sep [ppr_reason why,
- nest 2 (ppr_defn (nameSrcLoc name))]
-
-ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
-ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
-
-ppr_defn loc | isGoodSrcLoc loc = parens (ptext SLIT("at") <+> ppr loc)
- | otherwise = empty
-\end{code}