Zap stray whitespace in lhs formatting

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

diff --git a/compiler/typecheck/TcPat.lhs b/compiler/typecheck/TcPat.lhs
index e1a1f24..933adb8 100644 (file)
--- a/compiler/typecheck/TcPat.lhs
+++ b/compiler/typecheck/TcPat.lhs
@@ -279,7 +279,9 @@ tc_lpat :: LPat Name
 tc_lpat (L span pat) pat_ty pstate thing_inside
   = setSrcSpan span              $
     maybeAddErrCtxt (patCtxt pat) $
-    do { let (coercion, pat_ty') = refineType (pat_reft pstate) pat_ty
+    do { let mb_reft = refineType (pat_reft pstate) pat_ty
+             pat_ty' = case mb_reft of { Just (_, ty') -> ty'; Nothing -> pat_ty }
+
                -- Make sure the result type reflects the current refinement
                -- We must do this here, so that it correctly ``sees'' all
                -- the refinements to the left.  Example:
@@ -289,7 +291,10 @@ tc_lpat (L span pat) pat_ty pstate thing_inside
                -- pattern had better see it.
 
        ; (pat', tvs, res) <- tc_pat pstate pat pat_ty' thing_inside
-       ; return (mkCoPat coercion (L span pat') pat_ty, tvs, res) }
+       ; let final_pat = case mb_reft of
+                               Nothing     -> pat'
+                               Just (co,_) -> CoPat (WpCo co) pat' pat_ty
+       ; return (L span final_pat, tvs, res) }
 
 --------------------
 tc_pat :: PatState
@@ -526,14 +531,14 @@ tcConPat :: PatState -> SrcSpan -> DataCon -> TyCon
         -> HsConDetails Name (LPat Name) -> (PatState -> TcM a)
         -> TcM (Pat TcId, [TcTyVar], a)
 tcConPat pstate con_span data_con tycon pat_ty arg_pats thing_inside
-  = do { span <- getSrcSpanM   -- Span for the whole pattern
-       ; let (univ_tvs, ex_tvs, eq_spec, theta, arg_tys) = dataConFullSig data_con
-             skol_info = PatSkol data_con span
+  = do { let (univ_tvs, ex_tvs, eq_spec, theta, arg_tys) = dataConFullSig data_con
+             skol_info = PatSkol data_con
              origin    = SigOrigin skol_info
 
          -- Instantiate the constructor type variables [a->ty]
        ; ctxt_res_tys <- boxySplitTyConAppWithFamily tycon pat_ty
-       ; ex_tvs' <- tcInstSkolTyVars skol_info ex_tvs
+       ; ex_tvs' <- tcInstSkolTyVars skol_info ex_tvs  -- Get location from monad,
+                                                       -- not from ex_tvs
        ; let tenv     = zipTopTvSubst (univ_tvs ++ ex_tvs)
                                      (ctxt_res_tys ++ mkTyVarTys ex_tvs')
              eq_spec' = substEqSpec tenv eq_spec
@@ -548,7 +553,8 @@ tcConPat pstate con_span data_con tycon pat_ty arg_pats thing_inside
 
        ; loc <- getInstLoc origin
        ; dicts <- newDictBndrs loc theta'
-       ; dict_binds <- tcSimplifyCheck doc ex_tvs' dicts lie_req
+       ; dict_binds <- tcSimplifyCheckPat loc co_vars (pat_reft pstate') 
+                                          ex_tvs' dicts lie_req
 
        ; addDataConStupidTheta data_con ctxt_res_tys
 
@@ -562,8 +568,6 @@ tcConPat pstate con_span data_con tycon pat_ty arg_pats thing_inside
             ex_tvs' ++ inner_tvs, res)
        }
   where
-    doc = ptext SLIT("existential context for") <+> quotes (ppr data_con)
-
     -- Split against the family tycon if the pattern constructor belongs to a
     -- representation tycon.
     --