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"use strict";
const assert = require('assert');
const lua = require('./lua.js');
const lapi = require('./lapi.js');
const lauxlib = require('./lauxlib.js');
const CT = lua.constant_types;
const TS = lua.thread_status;
const str_len = function(L) {
lapi.lua_pushinteger(L, lauxlib.luaL_checkstring(L, 1).length);
return 1;
};
const str_char = function(L) {
let n = lapi.lua_gettop(L); /* number of arguments */
let p = "";
for (let i = 1; i <= n; i++) {
let c = lauxlib.luaL_checkinteger(L, i);
lauxlib.luaL_argcheck(L, c >= 0 && c <= 255, "value out of range"); // Strings are 8-bit clean
p += String.fromCharCode(c);
}
lapi.lua_pushstring(L, p);
return 1;
};
const strlib = {
"len": str_len,
"char": str_char
};
const createmetatable = function(L) {
lapi.lua_createtable(L, 0, 1); /* table to be metatable for strings */
lapi.lua_pushliteral(L, ""); /* dummy string */
lapi.lua_pushvalue(L, -2); /* copy table */
lapi.lua_setmetatable(L, -2); /* set table as metatable for strings */
lapi.lua_pop(L, 1); /* pop dummy string */
lapi.lua_pushvalue(L, -2); /* get string library */
lapi.lua_setfield(L, -2, "__index"); /* metatable.__index = string */
lapi.lua_pop(L, 1); /* pop metatable */
};
const luaopen_string = function(L) {
lauxlib.luaL_newlib(L, strlib);
createmetatable(L);
return 1;
};
module.exports.luaopen_string = luaopen_string;
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