From bb8442c975cd6b9f70c3f15cc09b2925594b11e1 Mon Sep 17 00:00:00 2001
From: simonmar <unknown>
Date: Thu, 17 Aug 2000 16:28:44 +0000
Subject: [PATCH] [project @ 2000-08-17 16:28:44 by simonmar] Replace a
 zipEqual with a zip in tcPat when checking a record pat.
 The former version caused a panic with DEBUG on if a record
 pattern was used with a non-record constructor.

---
 ghc/compiler/typecheck/TcPat.lhs |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/ghc/compiler/typecheck/TcPat.lhs b/ghc/compiler/typecheck/TcPat.lhs
index e0cb157..e5b8847 100644
--- a/ghc/compiler/typecheck/TcPat.lhs
+++ b/ghc/compiler/typecheck/TcPat.lhs
@@ -213,9 +213,11 @@ tcPat tc_bndr pat@(RecPatIn name rpats) pat_ty
  	-- Check the constructor itself
     tcConstructor pat name pat_ty	`thenTc` \ (data_con, ex_tvs, dicts, lie_avail1, arg_tys) ->
     let
-	field_tys = zipEqual "tcPat" 
-			     (map fieldLabelName (dataConFieldLabels data_con))
-			     arg_tys
+	-- not zipEqual: if the constructor isn't really a record, then
+	-- dataConFieldLabels will be empty (and each field in the pattern
+	-- will generate an error below).
+	field_tys = zip (map fieldLabelName (dataConFieldLabels data_con))
+			arg_tys
     in
 
 	-- Check the fields
-- 
1.7.10.4