是否有可能require()使用luaL_loadstring()加载的脚本? [英] Is it possible to require() a script that is loaded using luaL_loadstring()?

问题描述

我是Lua的初学者.

我想知道是否可以使用require('filename')要求使用luaL_loadstring()加载的脚本.

I wonder if it is possible to use require('filename') to require a script that is loaded using luaL_loadstring().

由于luaL_loadstring(lua_State *L, const char *s)没有指定任何文件名，所以我不知道如何使用require()从其他脚本加载该脚本.

Since luaL_loadstring(lua_State *L, const char *s) doesn't specify any filename, I don't know how to use require() to load this script from other script.

require()仅适用于实际的.lua文件吗?

Does require() only works with actual .lua files?

推荐答案

luaL_loadstring创建一个Lua函数，该函数在被调用时将执行给定的字符串.我们可以使用这个事实，因为Lua C模块还简单地调用函数luaopen_MODULE.此函数返回包含模块内容的表.也就是说，如果我们想通过luaL_loadstring加载模块，则以字符串形式给出的脚本必须返回一个表.剩下要做的唯一一件事就是让解释器知道在哪里可以找到模块.因此，我们只需在package.preload中创建一个条目.

luaL_loadstring creates a Lua function which, when called, executes the string it was given. We can use this fact, because Lua C modules also simply call a function luaopen_MODULE. This function returns a table with the module content. That is to say, if we want to load a module via luaL_loadstring the script given as a string has to return a table. The only thing left to do is letting the interpreter know where to find the module. Therefore we simply create an entry in package.preload.

有趣的部分在破折号之间.剩下的只是使解释器运行的样板. (可能无法在5.1中使用)

The interesting part is between the dashes. The rest is just boilerplate to get the interpreter running. (Might not work in 5.1)

#include <stdio.h>

#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>

int main(int argc, char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "Usage: %s <script.lua>\n", argv[0]);
        return 1;
    }

    lua_State * L = luaL_newstate();
    luaL_openlibs(L);

    // ---- Register our "fromstring" module ----
    lua_getglobal(L, "package");
    lua_getfield(L, -1, "preload");
    luaL_loadstring(L, "return { test = function() print('Test') end }");
    lua_setfield(L, -2, "fromstring");
    // ------------------------------------------

    if (luaL_dofile(L, argv[1]) != 0) {
        fprintf(stderr,"lua: %s\n", lua_tostring(L, -1));
        lua_close(L);
        return 1;
    }

    lua_close(L);
}

输入脚本:

local fromstring = require("fromstring")
fromstring.test()

输出:

Test

这篇关于是否有可能require()使用luaL_loadstring()加载的脚本?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！