利用LL分析方法实现的语法分析器。语法分析器（Parser）通常是作为编译器或解释器的组件出现的，它的作用是进行语法检查、并构建由输入的单词组成的数据结构（一般是语法分析树、抽象语法树等层次化的数据结构）。语法分析器通常使用一个独立的词法分析器从输入字符流中分离出一个个的“单词”，并将单词流作为其输入。-LL-implemented method of analysis utilizing the parser. Parser (Parser) is often used as a compiler or interpreter component appears, it is the role of syntax checking, and build a data structure composed by word input (usually parse tree, abstract syntax trees hierarchy data structure). Parser typically use a separate lexical analyzer separated one by one " word"　character　the input stream, and the stream of words as its input.