Complete the evidence generation for GADTs

[ghc-hetmet.git] / compiler / deSugar / DsArrows.lhs

diff --git a/compiler/deSugar/DsArrows.lhs b/compiler/deSugar/DsArrows.lhs
index 3484a5d..d477eff 100644 (file)
--- a/compiler/deSugar/DsArrows.lhs
+++ b/compiler/deSugar/DsArrows.lhs
@@ -513,8 +513,8 @@ dsCmd ids local_vars env_ids stack res_ty (HsCase exp (MatchGroup matches match_
     let
        left_id  = HsVar (dataConWrapId left_con)
        right_id = HsVar (dataConWrapId right_con)
-       left_expr  ty1 ty2 e = noLoc $ HsApp (noLoc $ HsCoerce (CoTyApps [ty1, ty2]) left_id ) e
-       right_expr ty1 ty2 e = noLoc $ HsApp (noLoc $ HsCoerce (CoTyApps [ty1, ty2]) right_id) e
+       left_expr  ty1 ty2 e = noLoc $ HsApp (noLoc $ HsCoerce (mkCoTyApps [ty1, ty2]) left_id ) e
+       right_expr ty1 ty2 e = noLoc $ HsApp (noLoc $ HsCoerce (mkCoTyApps [ty1, ty2]) right_id) e
 
        -- Prefix each tuple with a distinct series of Left's and Right's,
        -- in a balanced way, keeping track of the types.