一个简单的Lua解释器

#include "stdafx.h"

#include<stdarg.h>
#include<stdlib.h>
#include<stdio.h>
#include<string.h>    
#include<math.h>

#include<errno.h>
extern "C"{
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
}

lua_State *L;

void errormethod(const char *fmt, ...){
        va_list argp;
        va_start(argp, fmt);
        vfprintf(stderr, fmt, argp);
        va_end(argp);
        lua_close(L);
        //exit(EXIT_FAILURE);
}

static int l_sin(lua_State* L){
        //double d = lua_tonumber(L, 1);
        double d = luaL_checknumber(L, 1);
        lua_pushnumber(L, sin(d));
        //printf("call1 %f\n", d);
        return 1;
} 

static int add(lua_State* L){
        int n1 = lua_tonumber(L, 1);
        int n2 = lua_tonumber(L, 2);
        int sum = n1 + n2;
        lua_pushnumber(L, sum);
        //printf("call2 %f\n", d);  
        return 1;
} 
  
int main(int argc, char* argv[])
{
        char buff[256];
        int error;
        L = luaL_newstate();//创建Lua环境
        luaL_openlibs(L);//加载标准库
        lua_pushcfunction(L, l_sin);
        lua_setglobal(L, "mysin");
        lua_pushcfunction(L, add);
        lua_setglobal(L, "add");
                
        while(fgets(buff, sizeof(buff), stdin) != NULL){
                error = luaL_loadbuffer(L, buff, strlen(buff), "line") || lua_pcall(L, 0, 0, 0);
                if(error){  
                        //errormethod("%s\n", lua_tostring(L, -1));
                        fprintf(stderr, "%s\n", lua_tostring(L, -1));
                        lua_pop(L, -1);
                }
  
        }
//      lua_close(L);
        system("pause");
        return 0;
}

From Lua程序设计..

给我的认识是

Lua仅仅是一门嵌入式的脚本语言

需要宿主语言去启动它。