fix: 解决以数字开头的字符串变量KEY解析报错问题

[haihaoge]

No description provided.

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[CLAassistant]

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[DQinYuan]

补充下单元测试。
另外，变量不能以数字开头，在 Java 里也是有这种规范，建议和 Java 一致。
规避以数字开头的 key，数字尽量放到结尾。