Tests for identifier validity. First symbol must be alphabetic and remaining symbols must be alphanumeric. This tester program only checks identifiers that are at least two characters in length.是什么意思_Tests for identifier validity. First symbol must be alphabetic and remaining symbols must be alphanumeric. This tester program only checks identifiers that are at least two characters in length.在线翻译_英语_读音_用法_例句