[project @ 2003-04-22 09:30:52 by simonpj]

Stage-2 wibbles to the Expected type changes

diff --git a/ghc/compiler/typecheck/TcSplice.hi-boot-6 b/ghc/compiler/typecheck/TcSplice.hi-boot-6
index ae8183c..4c6483c 100644 (file)
--- a/ghc/compiler/typecheck/TcSplice.hi-boot-6
+++ b/ghc/compiler/typecheck/TcSplice.hi-boot-6
@@ -2,11 +2,11 @@ module TcSplice where
 
 tcSpliceExpr :: Name.Name
             -> RnHsSyn.RenamedHsExpr
-            -> TcType.TcType
+            -> TcUnify.Expected TcType.TcType
             -> TcRnTypes.TcM TcHsSyn.TcExpr
 
 tcBracket :: HsExpr.HsBracket Name.Name 
-         -> TcType.TcType
+         -> TcUnify.Expected TcType.TcType
          -> TcRnTypes.TcM TcHsSyn.TcExpr
 
 tcSpliceDecls :: RnHsSyn.RenamedHsExpr 

diff --git a/ghc/compiler/typecheck/TcSplice.lhs b/ghc/compiler/typecheck/TcSplice.lhs
index 6a2c4d7..17ca215 100644 (file)
--- a/ghc/compiler/typecheck/TcSplice.lhs
+++ b/ghc/compiler/typecheck/TcSplice.lhs
@@ -21,14 +21,14 @@ import Convert              ( convertToHsExpr, convertToHsDecls )
 import RnExpr          ( rnExpr )
 import RdrHsSyn                ( RdrNameHsExpr, RdrNameHsDecl )
 import RnHsSyn         ( RenamedHsExpr )
-import TcExpr          ( tcCheckRho )
+import TcExpr          ( tcCheckRho, tcMonoExpr )
 import TcHsSyn         ( TcExpr, TypecheckedHsExpr, mkHsLet, zonkTopExpr )
 import TcSimplify      ( tcSimplifyTop, tcSimplifyBracket )
-import TcUnify         ( unifyTauTy )
+import TcUnify         ( Expected, unifyTauTy, zapExpectedTo, zapExpectedType )
 import TcType          ( TcType, openTypeKind, mkAppTy )
 import TcEnv           ( spliceOK, tcMetaTy, tcWithTempInstEnv, bracketOK )
 import TcRnTypes       ( TopEnv(..) )
-import TcMType         ( newTyVarTy, zapToType, UserTypeCtxt(ExprSigCtxt) )
+import TcMType         ( newTyVarTy, UserTypeCtxt(ExprSigCtxt) )
 import TcMonoType      ( tcHsSigType )
 import Name            ( Name )
 import TcRnMonad
@@ -54,7 +54,7 @@ tcSpliceDecls :: RenamedHsExpr -> TcM [RdrNameHsDecl]
 
 tcSpliceExpr :: Name 
             -> RenamedHsExpr
-            -> TcType
+            -> Expected TcType
             -> TcM TcExpr
 
 #ifndef GHCI
@@ -70,7 +70,7 @@ tcSpliceDecls e     = pprPanic "Cant do tcSpliceDecls without GHCi" (ppr e)
 %************************************************************************
 
 \begin{code}
-tcBracket :: HsBracket Name -> TcType -> TcM TcExpr
+tcBracket :: HsBracket Name -> Expected TcType -> TcM TcExpr
 tcBracket brack res_ty
   = getStage                           `thenM` \ level ->
     case bracketOK level of {
@@ -88,7 +88,8 @@ tcBracket brack res_ty
     )                                  `thenM` \ (meta_ty, lie) ->
     tcSimplifyBracket lie              `thenM_`  
 
-    unifyTauTy res_ty meta_ty          `thenM_`
+       -- Make the expected type have the right shape
+    zapExpectedTo res_ty meta_ty       `thenM_`
 
        -- Return the original expression, not the type-decorated one
     readMutVar pending_splices         `thenM` \ pendings ->
@@ -144,7 +145,7 @@ tcSpliceExpr name expr res_ty
        -- Here (h 4) :: Q Exp
        -- but $(h 4) :: forall a.a     i.e. anything!
 
-    zapToType res_ty                           `thenM_`
+    zapExpectedType res_ty                     `thenM_`
     tcMetaTy exprTyConName                     `thenM` \ meta_exp_ty ->
     setStage (Splice next_level) (
        setLIEVar lie_var          $
@@ -162,7 +163,7 @@ tcSpliceExpr name expr res_ty
 -- Note that we do not decrement the level (to -1) before 
 -- typechecking the expression.  For example:
 --     f x = $( ...$(g 3) ... )
--- The recursive call to tcCheckRho will simply expand the 
+-- The recursive call to tcMonoExpr will simply expand the 
 -- inner escape before dealing with the outer one
 
 tcTopSplice expr res_ty
@@ -188,7 +189,7 @@ tcTopSplice expr res_ty
     initRn SourceMode (rnExpr expr2)           `thenM` \ (exp3, fvs) ->
     importSupportingDecls fvs                  `thenM` \ env ->
 
-    setGblEnv env (tcCheckRho exp3 res_ty)
+    setGblEnv env (tcMonoExpr exp3 res_ty)
 
 
 tcTopSpliceExpr :: RenamedHsExpr -> TcType -> TcM TypecheckedHsExpr