[project @ 1999-05-18 15:03:33 by simonpj]

[ghc-hetmet.git] / ghc / compiler / basicTypes / Var.lhs

diff --git a/ghc/compiler/basicTypes/Var.lhs b/ghc/compiler/basicTypes/Var.lhs
index cacde2b..4d5be70 100644 (file)
--- a/ghc/compiler/basicTypes/Var.lhs
+++ b/ghc/compiler/basicTypes/Var.lhs
@@ -5,10 +5,9 @@
 
 \begin{code}
 module Var (
-       Var, IdOrTyVar,         -- Abstract
-       VarDetails(..),         -- Concrete
-       varName, varUnique, varDetails, varInfo, varType,
-       setVarName, setVarUnique, setVarType,  setVarOcc,
+       Var, IdOrTyVar, VarDetails,             -- Abstract
+       varName, varUnique, varInfo, varType,
+       setVarName, setVarUnique, setVarType, setVarOcc,
 
 
        -- TyVars
@@ -26,18 +25,16 @@ module Var (
 
        -- Ids
        Id, DictId,
-       idDetails, idName, idType, idUnique, idInfo, modifyIdInfo,
+       idName, idType, idUnique, idInfo, modifyIdInfo, maybeModifyIdInfo,
        setIdName, setIdUnique, setIdInfo,
-       mkId, isId, externallyVisibleId
+       mkIdVar, isId, externallyVisibleId
     ) where
 
 #include "HsVersions.h"
 
 import {-# SOURCE #-}  Type( Type, Kind )
 import {-# SOURCE #-}  IdInfo( IdInfo )
-import {-# SOURCE #-}  Const( Con )
 
-import FieldLabel      ( FieldLabel )
 import Unique          ( Unique, Uniquable(..), mkUniqueGrimily, getKey )
 import Name            ( Name, OccName, NamedThing(..),
                          setNameUnique, setNameOcc, nameUnique, 
@@ -78,9 +75,7 @@ data Var
     }
 
 data VarDetails
-  = VanillaId                          -- Most Ids are like this
-  | ConstantId Con                     -- The Id for a constant (data constructor or primop)
-  | RecordSelId FieldLabel             -- The Id for a record selector
+  = AnId
   | TyVar
   | MutTyVar (IORef (Maybe Type))      -- Used during unification;
             Bool                       -- True <=> this is a type signature variable, which
@@ -164,7 +159,7 @@ mkTyVar name kind = Var { varName    = name
                        , varType    = kind
                        , varDetails = TyVar
 #ifdef DEBUG
-                       , varInfo = pprPanic "mkTyVar" (ppr name)
+                       , varInfo = pprPanic "looking at IdInfo of a tyvar" (ppr name)
 #endif
                        }
 
@@ -264,7 +259,6 @@ idName    = varName
 idType    = varType
 idUnique  = varUnique
 idInfo   = varInfo
-idDetails = varDetails
 
 setIdUnique :: Id -> Unique -> Id
 setIdUnique = setVarUnique
@@ -275,24 +269,27 @@ setIdName = setVarName
 setIdInfo :: Id -> IdInfo -> Id
 setIdInfo var info = var {varInfo = info}
 
-modifyIdInfo :: Id -> (IdInfo -> IdInfo) -> Id
-modifyIdInfo var@(Var {varInfo = info}) fn = var {varInfo = fn info}
+modifyIdInfo :: (IdInfo -> IdInfo) -> Id -> Id
+modifyIdInfo fn var@(Var {varInfo = info}) = var {varInfo = fn info}
+
+-- maybeModifyIdInfo tries to avoid unnecesary thrashing
+maybeModifyIdInfo :: (IdInfo -> Maybe IdInfo) -> Id -> Id
+maybeModifyIdInfo fn var@(Var {varInfo = info}) = case fn info of
+                                               Nothing       -> var
+                                               Just new_info -> var {varInfo = new_info}
 \end{code}
 
 \begin{code}
-mkId :: Name -> Type -> VarDetails -> IdInfo -> Id
-mkId name ty details info
+mkIdVar :: Name -> Type -> IdInfo -> Id
+mkIdVar name ty info
   = Var {varName = name, realUnique = getKey (nameUnique name), varType = ty, 
-        varDetails = details, varInfo = info}
+        varDetails = AnId, varInfo = info}
 \end{code}
 
 \begin{code}
 isId :: Var -> Bool
-isId (Var {varDetails = details}) = case details of
-                                       VanillaId     -> True
-                                       ConstantId _  -> True
-                                       RecordSelId _ -> True
-                                       other         -> False
+isId (Var {varDetails = AnId}) = True
+isId other                    = False
 \end{code}
 
 @externallyVisibleId@: is it true that another module might be