Where does the "exports" define in PhantomJS?

Question

Take a code segment of the fs.js for example:

exports.write = function (path, content, modeOrOpts) {
    var opts = modeOrOptsToOpts(modeOrOpts);
    // ensure we open for writing
    if ( typeof opts.mode !== 'string' ) {
        opts.mode = 'w';
    } else if ( opts.mode.indexOf('w') == -1 ) {
        opts.mode += 'w';
    }
    var f = exports.open(path, opts);

    f.write(content);
    f.close();
};

Now I'm confused with the exports object. You can find it in every PhantomJS module but I found no where to define the exports object.

Could anyone give me some suggestions about the place where defined the exports object?

---

Don't be confused with the exports in NodeJS. It's PhantomJS...

Answer 1

phantomJS实现了require语法（与NodeJS相同）

如果要包含外部库，则该库注入module对象，module.exports是require函数返回的公共对象。

//myMoudle.js

var _a = 5; //this is private member of the module 

module.exports= {
    a : ()=>{
      return _a;
    },
    setA : newA=>_a=newA;
}

要求：

//someCode.js
var myModule = require('path/to/myModule')
myModule.a() //5
myModule._a //undefined
myModule.setA(6) //_a is now 6

PhantomJS docs示例 requiring webpage module:

var webPage = require('webpage'); //included the module https://github.com/ariya/phantomjs/blob/master/src/modules/webpage.js 
var page = webPage.create();

包含webPage模块，在此模块中有下一个代码

exports.create = function (opts) {
    return decorateNewPage(opts, phantom.createWebPage());
};

允许在我们使用webPage.create函数

的地方使用require函数