This BIG PATCH contains most of the work for the New Coercion Representation

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

diff --git a/compiler/basicTypes/Id.lhs b/compiler/basicTypes/Id.lhs
index fd65fe4..5ac2612 100644 (file)
--- a/compiler/basicTypes/Id.lhs
+++ b/compiler/basicTypes/Id.lhs
@@ -23,7 +23,7 @@
 -- * 'Var.Var': see "Var#name_types"
 module Id (
         -- * The main types
-       Id, DictId,
+       Var, Id, isId,
 
        -- ** Simple construction
        mkGlobalId, mkVanillaGlobal, mkVanillaGlobalWithInfo,
@@ -34,8 +34,7 @@ module Id (
 
        -- ** Taking an Id apart
        idName, idType, idUnique, idInfo, idDetails,
-       isId, idPrimRep,
-       recordSelectorFieldLabel,
+       idPrimRep, recordSelectorFieldLabel,
 
        -- ** Modifying an Id
        setIdName, setIdUnique, Id.setIdType, 
@@ -46,7 +45,8 @@ module Id (
        
 
        -- ** Predicates on Ids
-       isImplicitId, isDeadBinder, isDictId, isStrictId,
+       isImplicitId, isDeadBinder, 
+        isStrictId,
        isExportedId, isLocalId, isGlobalId,
        isRecordSelector, isNaughtyRecordSelector,
         isClassOpId_maybe, isDFunId, dfunNSilent,
@@ -57,6 +57,9 @@ module Id (
         isTickBoxOp, isTickBoxOp_maybe,
        hasNoBinding, 
 
+       -- ** Evidence variables
+       DictId, isDictId, isEvVar, evVarPred,
+
        -- ** Inline pragma stuff
        idInlinePragma, setInlinePragma, modifyInlinePragma,
         idInlineActivation, setInlineActivation, idRuleMatchInfo,
@@ -95,8 +98,8 @@ import IdInfo
 import BasicTypes
 
 -- Imported and re-exported 
-import Var( Var, Id, DictId,
-            idInfo, idDetails, globaliseId,
+import Var( Var, Id, DictId, EvVar,
+            idInfo, idDetails, globaliseId, varType,
             isId, isLocalId, isGlobalId, isExportedId )
 import qualified Var
 
@@ -372,10 +375,6 @@ idDataCon :: Id -> DataCon
 -- INVARIANT: @idDataCon (dataConWrapId d) = d@: remember, 'dataConWrapId' can return either the wrapper or the worker
 idDataCon id = isDataConId_maybe id `orElse` pprPanic "idDataCon" (ppr id)
 
-
-isDictId :: Id -> Bool
-isDictId id = isDictTy (idType id)
-
 hasNoBinding :: Id -> Bool
 -- ^ Returns @True@ of an 'Id' which may not have a
 -- binding, even though it is defined in this module.
@@ -448,6 +447,26 @@ isTickBoxOp_maybe id =
 
 %************************************************************************
 %*                                                                     *
+              Evidence variables                                                                       
+%*                                                                     *
+%************************************************************************
+
+\begin{code}
+isEvVar :: Var -> Bool
+isEvVar var = isPredTy (varType var)
+
+isDictId :: Id -> Bool
+isDictId id = isDictTy (idType id)
+
+evVarPred :: EvVar -> PredType
+evVarPred var
+  = case splitPredTy_maybe (varType var) of
+      Just pred -> pred
+      Nothing   -> pprPanic "evVarPred" (ppr var <+> ppr (varType var))
+\end{code}
+
+%************************************************************************
+%*                                                                     *
 \subsection{IdInfo stuff}
 %*                                                                     *
 %************************************************************************