X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fcore%2Fmaputils.h;h=2495a1e29b41854e62850324d80fa358ffe2e152;hb=b4664bc8a51e2b78e9325feecc196a426ac4fc38;hp=8c642fb9c57a1f9acda6ba5ab2d0dc5311316306;hpb=1e0abc3a49ade6a4fa1b38f744df070c40a87724;p=libs%2Fcore.git

diff --git a/source/core/maputils.h b/source/core/maputils.h
index 8c642fb..2495a1e 100644
--- a/source/core/maputils.h
+++ b/source/core/maputils.h
@@ -9,11 +9,17 @@ namespace Msp {
 
 namespace MapUtilsInternal {
 
+/* This dummy struct is used to introduce a conversion, making the overloaded
+operator below worse than the templated one provided in lexicalcast.h. */
+struct Any
+{
+	template<typename T>
+	Any(const T &) { }
+};
+
 /* This must be hidden in the internal namespace to avoid interfering with
-other things.  There may be problems if a key type has operator<< for ostream
-but not LexicalConverter. */
-template<typename T>
-void operator<<(LexicalConverter &, const T &)
+other things. */
+inline void operator<<(LexicalConverter &, Any)
 { }
 
 template<typename T>
@@ -69,7 +75,7 @@ const typename T::mapped_type &get_item(const T &map, const typename T::key_type
 }
 
 template<typename T>
-const typename T::iterator insert_unique(T &map, const typename T::key_type &key, const typename T::mapped_type &item)
+typename T::iterator insert_unique(T &map, const typename T::key_type &key, const typename T::mapped_type &item)
 {
 	if(map.count(key))
 		throw key_error(key);
@@ -77,6 +83,15 @@ const typename T::iterator insert_unique(T &map, const typename T::key_type &key
 	return map.insert(typename T::value_type(key, item)).first;
 }
 
+template<typename T>
+void remove_existing(T &map, const typename T::key_type &key)
+{
+	if(!map.count(key))
+		throw key_error(key);
+
+	map.erase(key);
+}
+
 } // namespace Msp
 
 #endif