On Jul 12, 2013, at 12:14 PM, Jeremy Martin wrote:

> In brief: allow Symbol's to be constructed with a single parameter, with the following behavior:
> 
> > var obj = {};
> undefined
> > new Symbol({}) === new Symbol({})
> false
> > new Symbol(obj) === new Symbol(obj)
> true

You can use a WeakMap to build your own object-selected Symbol factory:

let known = new WeakMap;

function ObjSymFactory(obj) {
   //handle obj === undefined however you want
   let sym = known.get(obj);
   If (!sym) {
      sym = new Symbol;
      known.set(obj,sym);
   }
   return sym;
}

Allen   


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You can use a WeakMap to build your own object-selected Symbol factory:

```js
let known = new WeakMap;

function ObjSymFactory(obj) {
   //handle obj === undefined however you want
   let sym = known.get(obj);
   if (!sym) {
      sym = new Symbol;
      known.set(obj,sym);
   }
   return sym;
}
```

You can use a WeakMap to build your own object-selected Symbol factory:

```js
let known = new WeakMap;

function ObjSymFactory(obj) {
   //handle obj === undefined however you want
   let sym = known.get(obj);
   If (!sym) {
      sym = new Symbol;
      known.set(obj,sym);
   }
   return sym;
}
```