[project @ 1996-04-30 17:34:02 by partain]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcExpr.lhs

diff --git a/ghc/compiler/typecheck/TcExpr.lhs b/ghc/compiler/typecheck/TcExpr.lhs
index 6b2bec7..6454e1a 100644 (file)
--- a/ghc/compiler/typecheck/TcExpr.lhs
+++ b/ghc/compiler/typecheck/TcExpr.lhs
@@ -361,7 +361,7 @@ tcExpr (ExplicitTuple exprs)
 tcExpr (RecordCon (HsVar con) rbinds)
   = tcId con                           `thenNF_Tc` \ (con_expr, con_lie, con_tau) ->
     let
-       (_, record_ty)       = splitFunTy con_tau
+       (_, record_ty) = splitFunTy con_tau
     in
        -- Con is syntactically constrained to be a data constructor
     ASSERT( maybeToBool (maybeAppDataTyCon record_ty ) )
@@ -708,6 +708,12 @@ tcListComp expr (qual@(GeneratorQual pat rhs) : quals)
       tcAddErrCtxt (qualCtxt qual) (
         tcPat pat                              `thenTc` \ (pat',  lie_pat,  pat_ty)  ->
         tcExpr rhs                             `thenTc` \ (rhs', lie_rhs, rhs_ty) ->
+               -- NB: the environment has been extended with the new binders
+               -- which the rhs can't "see", but the renamer should have made
+               -- sure that everything is distinct by now, so there's no problem.
+               -- Putting the tcExpr before the newMonoIds messes up the nesting
+               -- of error contexts, so I didn't  bother
+
         unifyTauTy (mkListTy pat_ty) rhs_ty    `thenTc_`
        returnTc (GeneratorQual pat' rhs', 
                  lie_pat `plusLIE` lie_rhs)