public virtual IList <SrcOp> RuleRef(GrammarAST ID, GrammarAST label, GrammarAST args)
        {
            IList <SrcOp> ops = @delegate.RuleRef(ID, label, args);

            foreach (CodeGeneratorExtension ext in extensions)
            {
                ops = ext.RuleRef(ops);
            }
            return(ops);
        }