From ca5eb5186d003afe910463b20850a809c24961f0 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Tue, 15 Jan 2013 09:24:12 -0800
Subject: [PATCH] fix pretty printer for smt2 unary minus

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
---
 src/ast/ast_smt_pp.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/ast/ast_smt_pp.cpp b/src/ast/ast_smt_pp.cpp
index 66b467b92..3dc94d3b3 100644
--- a/src/ast/ast_smt_pp.cpp
+++ b/src/ast/ast_smt_pp.cpp
@@ -401,7 +401,12 @@ class smt_printer {
         if (m_autil.is_numeral(n, val, is_int)) {
             if (val.is_neg()) {
                 val.neg();
-                m_out << "(~ ";
+                if (m_is_smt2) {
+                    m_out << "(- ";
+                }
+                else {
+                    m_out << "(~ ";
+                }
                 display_rational(val, is_int);
                 m_out << ")";
             }