terminal: LEXER_ID | STRING

def visitLexerTerminal(self, ctx: jsgParser.LexerTerminalContext):
        """ terminal: LEXER_ID | STRING  """
        if ctx.LEXER_ID():
            # Substitute LEXER_ID with its string equivalent - "{LEXER_ID}".format(LEXER_ID=LEXER_ID.pattern)
            idtoken = as_token(ctx)
            self._rulePattern += '({' + idtoken + '})'
            self._ruleTokens.add(idtoken)
        else:
            self.add_string(ctx.getText()[1:-1], False)