From 985ebbadb94858d95211ae159cd6fe344e1c5d8f Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Thu, 6 Aug 2009 15:47:19 +0200
Subject: [PATCH] Let mkTupleShow support empty tuples.

---
 "c\316\273ash/CLasH/VHDL/VHDLTools.hs" | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git "a/c\316\273ash/CLasH/VHDL/VHDLTools.hs" "b/c\316\273ash/CLasH/VHDL/VHDLTools.hs"
index fbe33a7..b2416dc 100644
--- "a/c\316\273ash/CLasH/VHDL/VHDLTools.hs"
+++ "b/c\316\273ash/CLasH/VHDL/VHDLTools.hs"
@@ -575,13 +575,16 @@ mkTupleShow elemTMs tupleTM = AST.SubProgBody showSpec [] [showExpr]
     showExpr  = AST.ReturnSm (Just $
                   AST.PrimLit "'('" AST.:&: showMiddle AST.:&: AST.PrimLit "')'")
       where
-        showMiddle = foldr1 (\e1 e2 -> e1 AST.:&: AST.PrimLit "','" AST.:&: e2) $
-          map ((genExprFCall showId).
-                AST.PrimName .
-                AST.NSelected .
-                (AST.NSimple tupPar AST.:.:).
-                tupVHDLSuffix)
-              (take tupSize recordlabels)
+        showMiddle = if null elemTMs then
+            AST.PrimLit "''"
+          else
+            foldr1 (\e1 e2 -> e1 AST.:&: AST.PrimLit "','" AST.:&: e2) $
+              map ((genExprFCall showId).
+                    AST.PrimName .
+                    AST.NSelected .
+                    (AST.NSimple tupPar AST.:.:).
+                    tupVHDLSuffix)
+                  (take tupSize recordlabels)
     recordlabels = map (\c -> mkVHDLBasicId [c]) ['A'..'Z']
     tupSize = length elemTMs
 
-- 
2.30.2