checked set of alphabet

alib2data/src/alphabet/Alphabet.hpp

@@ -73,7 +73,8 @@ public:
 		for ( const SymbolType & symbol : removed )
 			remove ( symbol );
-		data = std::move ( symbols );
+		for ( const SymbolType & symbol : symbols )
+			add ( std::move ( symbols ) );
 	}
 	/**