code: public EvalError toEvalError(
          String msg, SimpleNode node, CallStack callstack  )
      {
          if ( null == msg )
              msg = this.getMessage();
          else
              msg += ": " + this.getMessage();
  
          return new TargetError( msg, this.getCause(), node, callstack, false );
      }
docs: Override toEvalError to throw TargetError type.