From 7438fa3c650ba8508068c38e651fc08c32d6b447 Mon Sep 17 00:00:00 2001
From: Alexandre Duret-Lutz <adl@lrde.epita.fr>
Date: Sat, 5 May 2012 11:05:58 +0200
Subject: [PATCH] Fix LTL output for Spin.

* src/ltlvisit/tostring.cc (spin_kw): Output X, not ().
---
 src/ltlvisit/tostring.cc | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/ltlvisit/tostring.cc b/src/ltlvisit/tostring.cc
index eec5142aa..bc99c6457 100644
--- a/src/ltlvisit/tostring.cc
+++ b/src/ltlvisit/tostring.cc
@@ -105,11 +105,11 @@ namespace spot
 	"1",
 	"[*0]",			// not supported
 	" xor ",		// rewritten
-	" -> ",			// rewritten
-	" <-> ",		// rewritten
+	" -> ",			// rewritten, although supported
+	" <-> ",		// rewritten, although supported
 	" U ",
 	" V ",
-	" W ",			// rewritten
+	" W ",			// rewritten, although supported
 	" M ",			// rewritten
 	"<>-> ",		// not supported
 	"<>=> ",		// not supported
@@ -118,7 +118,7 @@ namespace spot
 	"[]-> ",		// not supported
 	"[]=> ",		// not supported
 	"!",
-	"()",
+	"X",
 	"<>",
 	"[]",
 	" || ",