[project @ 2001-10-18 16:29:12 by simonpj]

[ghc-hetmet.git] / ghc / compiler / main / HscTypes.lhs

diff --git a/ghc/compiler/main/HscTypes.lhs b/ghc/compiler/main/HscTypes.lhs
index 95904c9..c29421c 100644 (file)
--- a/ghc/compiler/main/HscTypes.lhs
+++ b/ghc/compiler/main/HscTypes.lhs
@@ -5,6 +5,8 @@
 
 \begin{code}
 module HscTypes ( 
+       GhciMode(..),
+
        ModuleLocation(..),
 
        ModDetails(..), ModIface(..), 
@@ -24,11 +26,11 @@ module HscTypes (
 
        TypeEnv, lookupType, mkTypeEnv, emptyTypeEnv,
        extendTypeEnvList, extendTypeEnvWithIds,
-       typeEnvClasses, typeEnvTyCons, typeEnvIds,
+       typeEnvElts, typeEnvClasses, typeEnvTyCons, typeEnvIds,
 
        ImportedModuleInfo, WhetherHasOrphans, ImportVersion, WhatsImported(..),
        PersistentRenamerState(..), IsBootInterface, DeclsMap,
-       IfaceInsts, IfaceRules, GatedDecl, IsExported,
+       IfaceInsts, IfaceRules, GatedDecl, GatedDecls, GateFn, IsExported,
        NameSupply(..), OrigNameCache, OrigIParamCache,
        Avails, AvailEnv, GenAvailInfo(..), AvailInfo, RdrAvailInfo, 
        PersistentCompilerState(..),
@@ -62,7 +64,7 @@ import Rules          ( RuleBase )
 import CoreSyn         ( CoreBind )
 import Id              ( Id )
 import Class           ( Class, classSelIds )
-import TyCon           ( TyCon, tyConGenIds, tyConSelIds, tyConDataConsIfAvailable )
+import TyCon           ( TyCon, isNewTyCon, tyConGenIds, tyConSelIds, tyConDataConsIfAvailable )
 import DataCon         ( dataConId, dataConWrapId )
 
 import BasicTypes      ( Version, initialVersion, Fixity )
@@ -84,6 +86,18 @@ import UniqSupply    ( UniqSupply )
 
 %************************************************************************
 %*                                                                     *
+\subsection{Which mode we're in
+%*                                                                     *
+%************************************************************************
+
+\begin{code}
+data GhciMode = Batch | Interactive | OneShot 
+     deriving Eq
+\end{code}
+
+
+%************************************************************************
+%*                                                                     *
 \subsection{Module locations}
 %*                                                                     *
 %************************************************************************
@@ -93,7 +107,7 @@ data ModuleLocation
    = ModuleLocation {
         ml_hs_file   :: Maybe FilePath,
         ml_hspp_file :: Maybe FilePath,  -- path of preprocessed source
-        ml_hi_file   :: Maybe FilePath,
+        ml_hi_file   :: FilePath,
         ml_obj_file  :: Maybe FilePath
      }
      deriving Show
@@ -175,7 +189,7 @@ data ModDetails
 -- The ModDetails takes on several slightly different forms:
 --
 -- After typecheck + desugar
---     md_types        Contains TyCons, Classes, and hasNoBinding Ids
+--     md_types        Contains TyCons, Classes, and implicit Ids
 --     md_insts        All instances from this module (incl derived ones)
 --     md_rules        All rules from this module
 --     md_binds        Desugared bindings
@@ -207,13 +221,6 @@ data ModDetails
 \end{code}
 
 \begin{code}
-emptyModDetails :: ModDetails
-emptyModDetails
-  = ModDetails { md_types = emptyTypeEnv,
-                 md_insts = [],
-                 md_rules = []
-    }
-
 emptyModIface :: Module -> ModIface
 emptyModIface mod
   = ModIface { mi_module   = mod,
@@ -310,9 +317,16 @@ instance Outputable TyThing where
   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] 
+
+typeEnvElts    :: TypeEnv -> [TyThing]
+typeEnvClasses :: TypeEnv -> [Class]
+typeEnvTyCons  :: TypeEnv -> [TyCon]
+typeEnvIds     :: TypeEnv -> [Id]
+
+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] 
 
 implicitTyThingIds :: [TyThing] -> [Id]
 -- Add the implicit data cons and selectors etc 
@@ -324,8 +338,13 @@ implicitTyThingIds things
     go (ATyCon tc) = tyConGenIds tc ++
                     tyConSelIds tc ++
                     [ n | dc <- tyConDataConsIfAvailable tc, 
-                          n  <- [dataConId dc, dataConWrapId dc] ] 
+                          n  <- implicitConIds tc dc]
                -- Synonyms return empty list of constructors and selectors
+
+    implicitConIds tc dc       -- Newtypes have a constructor wrapper,
+                               -- but no worker
+       | isNewTyCon tc = [dataConWrapId dc]
+       | otherwise     = [dataConId dc, dataConWrapId dc]
 \end{code}
 
 
@@ -592,7 +611,13 @@ 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))
+type GatedDecl  d = (GateFn, (Module, d))
+type GateFn       = (Name -> Bool) -> Bool     -- Returns True <=> gate is open
+                                               -- The (Name -> Bool) fn returns True for visible Names
+       -- 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}
 
 
@@ -690,11 +715,11 @@ 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 (parens (ppr_defn (nameSrcLoc name)))]
+                                               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 = ptext SLIT("at") <+> ppr loc
+ppr_defn loc | isGoodSrcLoc loc = parens (ptext SLIT("at") <+> ppr loc)
             | otherwise        = empty
 \end{code}