Major refactoring of the type inference engine

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

diff --git a/compiler/typecheck/TcPat.lhs b/compiler/typecheck/TcPat.lhs
index a82584c..d28e901 100644 (file)
--- a/compiler/typecheck/TcPat.lhs
+++ b/compiler/typecheck/TcPat.lhs
@@ -669,10 +669,7 @@ tcConPat penv (L con_span con_name) pat_ty arg_pats thing_inside
        ; setSrcSpan con_span $ addDataConStupidTheta data_con ctxt_res_tys
 
        ; checkExistentials ex_tvs penv 
-        ; let skol_info = case pe_ctxt penv of
-                            LamPat mc -> PatSkol data_con mc
-                            LetPat {} -> UnkSkol -- Doesn't matter
-       ; ex_tvs' <- tcInstSkolTyVars skol_info ex_tvs  
+        ; ex_tvs' <- tcInstSuperSkolTyVars ex_tvs
                      -- Get location from monad, not from ex_tvs
 
         ; let pat_ty' = mkTyConApp tycon ctxt_res_tys
@@ -704,14 +701,17 @@ tcConPat penv (L con_span con_name) pat_ty arg_pats thing_inside
                            -- order is *important* as we generate the list of
                            -- dictionary binders from theta'
              no_equalities = not (any isEqPred theta')
-
+              skol_info = case pe_ctxt penv of
+                            LamPat mc -> PatSkol data_con mc
+                            LetPat {} -> UnkSkol -- Doesn't matter
+ 
         ; gadts_on <- xoptM Opt_GADTs
        ; checkTc (no_equalities || gadts_on)
                  (ptext (sLit "A pattern match on a GADT requires -XGADTs"))
                  -- Trac #2905 decided that a *pattern-match* of a GADT
                  -- should require the GADT language flag
 
-       ; given <- newEvVars theta'
+        ; given <- newEvVars theta'
         ; (ev_binds, (arg_pats', res))
             <- checkConstraints skol_info ex_tvs' given $
                 tcConArgs data_con arg_tys' arg_pats penv thing_inside