Proposal About Private Symbol

Gary Guo nbdd0121 at
Sun Dec 21 04:25:40 PST 2014

Oops, I forget the WeakSet. So seems my private symbol proposal can work now. Under very deliberately design, private symbol can be used as private field.
```jsvar constructor=function(){    'use strict';    var allObjects=new WeakSet();    var privateSymbol=Symbol('private', true);    var ret=function(){        if(this===undefined)throw Error('Invalid Construction');        this[privateSymbol]=1;        allObjects.add(this);    }    ret.prototype.set=function(sth){        if(!allObject.has(this))throw Error('Invalid Call');        this[privateSymbol]=sth; // Now this can be called safely, no more worry about leak to Proxy    }    ret.bind(undefined);}```
On Sun, 21 Dec 2014 12:30:46 +0100, Michal Wadas <michalwadas at> wrote:
>> But this is not the core of the problem. The problem is the Proxy introduced in ES6 enables an object to capture and override almost any operation on an object. Without operation on object, it becomes very costly (by using an Array of created objects and compare each of them) to identify whether a object is faked or valid.
>ES6 WeakSet provides you O(1) object check and don't cause memory leak.  		 	   		  
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