str: fix searching for a string parser group

alib2str/src/registry/StringReaderRegistry.cpp

@@ -32,9 +32,25 @@ std::shared_ptr < abstraction::OperationAbstraction > StringReaderRegistry::getA
 		return entry.first ( ss );
 	};
-	const auto & entryIterator = getEntries ( ).find ( group );
-	if ( entryIterator == getEntries ( ).end ( ) )
-		throw exception::CommonException ( "Entry " + group + " not available." );
+	auto entryIterator = getEntries ( ).end ( );
+	for ( auto iter = getEntries ( ).begin ( ); iter != getEntries ( ).end ( ); ++ iter )
+		if ( ext::is_same_type ( group, iter->first ) ) {
+			if ( entryIterator == getEntries ( ).end ( ) )
+				entryIterator = iter;
+			else
+				throw std::invalid_argument ( "Entry " + group + " is ambigous." );
+		}
+
+	if ( entryIterator == getEntries ( ).end ( ) ) {
+		std::stringstream entryList;
+		bool first = true;
+		for ( const auto & entry : getEntries ( ) ) {
+			entryList << ( ( ! first ) ? ", " : "" ) << entry.first;
+			first = false;
+		}
+
+		throw exception::CommonException ( "Entry " + group + " not available. Available entries are: " + entryList.str ( ) );
+	}
 	const auto & entries = entryIterator->second;