On Jul 16, 2013, at 4:41 PM, Mark S. Miller wrote:
>
>
> I like the general idea. But when actually called simply as a function, this
> would be unpleasant. Understanding that any ES5 behavior will be a compromise
> to prepare the ground for ES6, I suggest this variant:
>
> function MapConstructor() {
> if (%_IsConstructCall()) {
> %MapInitialize(this);
> } else if (this === void 0) {
this test isn't sufficient is you really want to support constructors as
callable factories. Consider an namespace object (or a module) such as:
let ES6 = {Map, WeakMap, Set};
ES6.Map();
> return new $Map();
> } else {
> throw ....;
> }
> }
>
> I already have a lot of code that simply calls WeakMap() without saying
> "new". I suspect that others will too by the time they see v8's new built-in
> WeakMaps.
We need to discourage leaving out the new, rather than trying to preserve the
small amount (in terms of web scale) of existing code that uses Map/Set/WeakMap
as callable factories.
Allen
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss
