该函数是词法分析程序的核心,它可以识别出源程序中的编写错误,以及找出关键字,变量等.具体请看源代码，注释很详细，但是肯定有不足的地方，请大家不吝赐教.-Lexical Analysis of the function is the core of the procedure, which can identify the source of the preparation of an error, and to identify keywords and other variables. For