Core: introduce Alt/AnnAlt/IfaceAlt datatypes

Alt, AnnAlt and IfaceAlt were using triples. This patch makes them use
dedicated types so that we can try to make some fields strict (for
example) in the future.

1 files changed, 6 insertions, 3 deletions

diff --git a/compiler/GHC/Core/Ppr.hs b/compiler/GHC/Core/Ppr.hs
index 37e5afc963..ddfa2ea2a6 100644
--- a/compiler/GHC/Core/Ppr.hs
+++ b/compiler/GHC/Core/Ppr.hs
@@ -68,6 +68,9 @@ instance OutputableBndr b => Outputable (Bind b) where
 instance OutputableBndr b => Outputable (Expr b) where
     ppr expr = pprCoreExpr expr
 
+instance OutputableBndr b => Outputable (Alt b) where
+    ppr expr = pprCoreAlt expr
+
 {-
 ************************************************************************
 *                                                                      *
@@ -221,7 +224,7 @@ ppr_expr add_par expr@(App {})
         _ -> parens (hang (pprParendExpr fun) 2 pp_args)
     }
 
-ppr_expr add_par (Case expr var ty [(con,args,rhs)])
+ppr_expr add_par (Case expr var ty [Alt con args rhs])
   = sdocOption sdocPrintCaseAsLet $ \case
       True -> add_par $  -- See Note [Print case as let]
                sep [ sep [ text "let! {"
@@ -299,8 +302,8 @@ ppr_expr add_par (Tick tickish expr)
       True  -> ppr_expr add_par expr
       False -> add_par (sep [ppr tickish, pprCoreExpr expr])
 
-pprCoreAlt :: OutputableBndr a => (AltCon, [a] , Expr a) -> SDoc
-pprCoreAlt (con, args, rhs)
+pprCoreAlt :: OutputableBndr a => Alt a -> SDoc
+pprCoreAlt (Alt con args rhs)
   = hang (ppr_case_pat con args <+> arrow) 2 (pprCoreExpr rhs)
 
 ppr_case_pat :: OutputableBndr a => AltCon -> [a] -> SDoc