+ typename TDecorated::const_iterator aIt = this->Get( ).find( a );
+ typename TDecorated::const_iterator bIt = this->Get( ).find( b );
+
+ if( aIt == this->Get( ).end( ) || bIt == this->Get( ).end( ) )
+ return;
+
+ short fa = aIt->second.second;
+ short fb = bIt->second.second;