From 509a59353c2e4a66e4ef6b18160c04e0e6929420 Mon Sep 17 00:00:00 2001
From: artemp <artem@mapnik.org>
Date: Mon, 19 May 2014 12:36:44 +0100
Subject: [PATCH] be more consistent with JS logic when evaluating operators on
 unicode_strings

'abc' + 'de' -> 'abcde'
'abc' ( - | * | / | % ) 'de' -> value_null
---
 include/mapnik/value.hpp | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/include/mapnik/value.hpp b/include/mapnik/value.hpp
index 087cc710e..4d0a5ad4b 100644
--- a/include/mapnik/value.hpp
+++ b/include/mapnik/value.hpp
@@ -425,7 +425,7 @@ struct sub : public boost::static_visitor<V>
     value_type operator() (value_unicode_string const& lhs,
                            value_unicode_string const& ) const
     {
-        return lhs;
+        return value_type();
     }
 
     value_type operator() (value_double lhs, value_integer rhs) const
@@ -462,7 +462,7 @@ struct mult : public boost::static_visitor<V>
     value_type operator() (value_unicode_string const& lhs,
                            value_unicode_string const& ) const
     {
-        return lhs;
+        return value_type();
     }
 
     value_type operator() (value_double lhs, value_integer rhs) const
@@ -510,7 +510,7 @@ struct div: public boost::static_visitor<V>
     value_type operator() (value_unicode_string const& lhs,
                            value_unicode_string const&) const
     {
-        return lhs;
+        return value_type();
     }
 
     value_type operator() (value_double lhs, value_integer rhs) const
@@ -545,7 +545,7 @@ struct mod: public boost::static_visitor<V>
     value_type operator() (value_unicode_string const& lhs,
                            value_unicode_string const&) const
     {
-        return lhs;
+        return value_type();
     }
 
     value_type operator() (value_bool lhs,
@@ -595,8 +595,7 @@ struct negate : public boost::static_visitor<V>
 
     value_type operator() (value_unicode_string const& ustr) const
     {
-        value_unicode_string inplace(ustr);
-        return inplace.reverse();
+        return value_type();
     }
 };