lexerRuleSpec: LEXER_ID COLON lexerRuleBlock SEMI

def visitLexerRuleSpec(self, ctx: jsgParser.LexerRuleSpecContext):
        """ lexerRuleSpec: LEXER_ID COLON lexerRuleBlock SEMI """
        self._context.grammarelts[as_token(ctx)] = JSGLexerRuleBlock(self._context, ctx.lexerRuleBlock())