一种改进的词法分析程序及其类C语言实现

Improved Lexical Analysis and Its Implementation in C-like Language

本文提出一种改进的词法分析程序设计思想,并进行了实现。首先定义四类字符集,构造状态转换矩阵。然后通过对给定文法的分析,化简变换状态转换矩阵使之成为程序可直接使用的二维数组Status。最后利用二维数组Status给出了核心函数get Word()的类C描述。

In this paper,the design thought of an improved lexical analysis is proposed and realized.First of all,the definition of four types of character sets and construction of a state transition matrix are achieved.Secondly,through analysis of a given grammar,the state transition matrix can be transformed into a two-dimensional array in which the lexical analysis can directly use.Finally,the description of core function getWord（）,which takes advantage of the matrix above,is given in C-like language.