编程实战：类C语法的编译型脚本解释器（七）语句

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编程实战：类C语法的编译型脚本解释器（系列）-CSDN博客

本文介绍语句，主要是控制语句，if、else、for之类。

一、语句概览

		//语句//EXPRESSION RETURN:expressions[0]//BLOCK:senetnces//IF:if(expressions[0])sentences[0] else sentences[1]//FOR:for(expressions[0];expressions[1];expressions[2])sentences[0]//DO:do sentences[0] while(expressions[0]);//WHILE:while(expressions[0])sentences[0]struct Sentence{enum types { NULLSENTENCE = 0, DECLARE, EXPRESSION, BLOCK, RETURN, IF, FOR, BREAK, CONTINUE, DO, WHILE };types type;size_t source_start;//起始位置size_t source_end;//结束位置vector<Expression > expressions;vector<Sentence > sentences;Sentence() { clear(); }void clear(){type = NULLSENTENCE;source_start = 0;source_end = 0;expressions.clear();sentences.clear();}bool isLoop()const { return FOR == type || DO == type || WHILE == type; }//inloop=true表示处于循环体内，可能从上层带入bool CheckSentence(string& source, T_VARIABLE_S& vars, bool _inloop);//若为return语句则设置bFinishbool ExecSentence(CZBScript const& script, T_VARIABLE_S& vars, bool& bFinish, bool& bBreak, bool& bContinue, Variable& ret, void* pe)const;string ToString(string const& source, T_VARIABLE_S const& vars, long level = 0)const;
};

语句比表达式简单多了。语句的类型更容易理解，大部分语句类型都是控制语句，有特殊的关键字对应，其余几个需要特别理解：