如何找到 browserify 的 `require` 函数的定义?
How can I find the definition of the `require` function of browserify?
在 browserify 捆绑文件中,我看到了这样的代码:
require = (function e(t, n, r) {
function s(o, u) {
if (!n[o]) {
if (!t[o]) {
var a = typeof require == "function" && require;
if (!u && a)
return a(o, !0);
if (i)
return i(o, !0);
throw new Error("Cannot find module '" + o + "'")
}
var f = n[o] = {exports: {}};
t[o][0].call(f.exports, function(e) {
var n = t[o][1][e];
return s(n ? n : e)
}, f, f.exports, e, t, n, r)
}
return n[o].exports
}
var i = typeof require == "function" && require;
for (var o = 0; o < r.length; o++)
s(r[o]);
return s
})(.........)
require
函数的定义看起来很短,但是我发现require
定义中的变量名好像变丑了。。在哪里可以找到definition/implementation的原始require
Browserify 的功能?
我想我在 node_modules/browserify/node_modules/browser-pack/prelude.js
找到了答案,但代码对我来说看起来很神秘.. 希望有人能给出更好的解释..
// modules are defined as an array
// [ module function, map of requireuires ]
//
// map of requireuires is short require name -> numeric require
//
// anything defined in a previous bundle is accessed via the
// orig method which is the requireuire for previous bundles
(function outer (modules, cache, entry) {
// Save the require from previous bundle to this closure if any
var previousRequire = typeof require == "function" && require;
function newRequire(name, jumped){
if(!cache[name]) {
if(!modules[name]) {
// if we cannot find the the module within our internal map or
// cache jump to the current global require ie. the last bundle
// that was added to the page.
var currentRequire = typeof require == "function" && require;
if (!jumped && currentRequire) return currentRequire(name, true);
// If there are other bundles on this page the require from the
// previous one is saved to 'previousRequire'. Repeat this as
// many times as there are bundles until the module is found or
// we exhaust the require chain.
if (previousRequire) return previousRequire(name, true);
var err = new Error('Cannot find module \'' + name + '\'');
err.code = 'MODULE_NOT_FOUND';
throw err;
}
var m = cache[name] = {exports:{}};
modules[name][0].call(m.exports, function(x){
var id = modules[name][1][x];
return newRequire(id ? id : x);
},m,m.exports,outer,modules,cache,entry);
}
return cache[name].exports;
}
for(var i=0;i<entry.length;i++) newRequire(entry[i]);
// Override the current require with this new one
return newRequire;
})
在 browserify 捆绑文件中,我看到了这样的代码:
require = (function e(t, n, r) {
function s(o, u) {
if (!n[o]) {
if (!t[o]) {
var a = typeof require == "function" && require;
if (!u && a)
return a(o, !0);
if (i)
return i(o, !0);
throw new Error("Cannot find module '" + o + "'")
}
var f = n[o] = {exports: {}};
t[o][0].call(f.exports, function(e) {
var n = t[o][1][e];
return s(n ? n : e)
}, f, f.exports, e, t, n, r)
}
return n[o].exports
}
var i = typeof require == "function" && require;
for (var o = 0; o < r.length; o++)
s(r[o]);
return s
})(.........)
require
函数的定义看起来很短,但是我发现require
定义中的变量名好像变丑了。。在哪里可以找到definition/implementation的原始require
Browserify 的功能?
我想我在 node_modules/browserify/node_modules/browser-pack/prelude.js
找到了答案,但代码对我来说看起来很神秘.. 希望有人能给出更好的解释..
// modules are defined as an array
// [ module function, map of requireuires ]
//
// map of requireuires is short require name -> numeric require
//
// anything defined in a previous bundle is accessed via the
// orig method which is the requireuire for previous bundles
(function outer (modules, cache, entry) {
// Save the require from previous bundle to this closure if any
var previousRequire = typeof require == "function" && require;
function newRequire(name, jumped){
if(!cache[name]) {
if(!modules[name]) {
// if we cannot find the the module within our internal map or
// cache jump to the current global require ie. the last bundle
// that was added to the page.
var currentRequire = typeof require == "function" && require;
if (!jumped && currentRequire) return currentRequire(name, true);
// If there are other bundles on this page the require from the
// previous one is saved to 'previousRequire'. Repeat this as
// many times as there are bundles until the module is found or
// we exhaust the require chain.
if (previousRequire) return previousRequire(name, true);
var err = new Error('Cannot find module \'' + name + '\'');
err.code = 'MODULE_NOT_FOUND';
throw err;
}
var m = cache[name] = {exports:{}};
modules[name][0].call(m.exports, function(x){
var id = modules[name][1][x];
return newRequire(id ? id : x);
},m,m.exports,outer,modules,cache,entry);
}
return cache[name].exports;
}
for(var i=0;i<entry.length;i++) newRequire(entry[i]);
// Override the current require with this new one
return newRequire;
})