On Fri Jun 13 2014 at 3:41:02 PM, Allen Wirfs-Brock <allen at wirfs-brock.com>
wrote:

>
> On Jun 13, 2014, at 12:07 PM, Jussi Kalliokoski wrote:
>
> >
> >
> > function Foo () {}
> >
> > Foo.prototype[Symbol.create] = null;
>
> @@create methods are normally defined as methods of the constructor
> function rather than as an instance method on the prototype. So the above
> should be:
>
> Foo[Symbol.create] = null;
>
> >
> > // ???
> > // Maybe error out, like currently host objects without [[Construct]]:
> > // TypeError: Foo is not a constructor.
> > new Foo();
>
> as currently specified [1] (and after I fix a bug I just noticed) it will
> fall back to doing the equivalent of Object.create().
>
> I did that to maximize backwards compatibility for this specific situation:
>
> function Foo() {};
> Foo.__proto__ = null; //in ES6 default @@create inherited from
> Function.prototype becomes unavailable
> new Foo;    //but in ES1-5 this still does the equivalent of
> Object.create();
>

Hold on. We covered this in one of the face to face meetings and I was of
the impression it was decided that we should not have a fallback but
instead throw.

https://github.com/rwaldron/tc39-notes/blob/48c5d285bf8bf0c4e6e8bb0c02a7c840c01cd2ff/es6/2013-01/jan-29.md#48-refactored-new-operator-and-the-create-method


> If we go down the route of eliminating [[Construct]] and are willing to
> break backwards compat. for this case, then we could make 'new' throw if a
> constructor doesn't have a callable @@create.  That would provide a good
> way to indicate that a function is not a constructor (which is current
> determine based upon it having a [[Construct]] internal method.
>
> Allen
>
>
>
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>
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On Fri Jun 13 2014 at 3:41:02 PM, Allen Wirfs-Brock <allen at wirfs-brock.com> wrote:

> I did that to maximize backwards compatibility for this specific situation:
>
> ```js
> function Foo() {};
> Foo.__proto__ = null; //in ES6 default @@create inherited from
> Function.prototype becomes unavailable
> new Foo;    //but in ES1-5 this still does the equivalent of
> Object.create();
> ```

Hold on. We covered this in one of the face to face meetings and I was of
the impression it was decided that we should not have a fallback but
instead throw.

https://github.com/rwaldron/tc39-notes/blob/48c5d285bf8bf0c4e6e8bb0c02a7c840c01cd2ff/es6/2013-01/jan-29.md#48