const {resolve} = Promise; // fails

[Michael Luder-Rosefield]

At this point I can't ignore how much overlap there is between this and the
this-binding operator proposal
https://github.com/tc39/proposal-bind-operator

```
const resolve = ::Promise.resolve; // takes and binds
```

As someone who often extracts functions with deconstruction, I'd love for
there to be an extension to this proposal to handle this case.

```
const { resolve, reject } = ::Promise; // ?
```

That would leave the question though of what to do with nesting:

```
const { fn1, foo: { fn2 } } = ::bar; // fn1 is bound to bar. Is fn2 bound
to bar, or foo?
```

On Thu, 19 Jul 2018 at 15:58 Andrea Giammarchi <andrea.giammarchi at gmail.com>
wrote:

> I guess one example would be more explicative: why cannot public static
> methods be defined in a similar manner?
>
> ```js
> const withLazyBoundObjects = new WeakMap;
> const withLazyBoundMethods = obj => {
>   const descriptors = Object.getOwnPropertyDescriptors(obj);
>   Object.keys(descriptors).forEach(key => {
>     const desc = descriptors[key];
>     const {value} = desc;
>     if (desc.configurable && typeof value === 'function') {
>       delete desc.value;
>       delete desc.writable;
>       desc.get = function (...args) {
>         let methods = withLazyBoundObjects.get(this || obj);
>         if (!methods)
>           withLazyBoundObjects.set(this, methods = Object.create(null));
>         return methods[key] || (methods[key] = value.bind(this));
>       };
>     }
>   });
>   return Object.defineProperties(obj, descriptors);
> };
>
> // example
> const {resolve, reject} = withLazyBoundMethods(Promise);
> resolve(123).then(console.log);
> ```
>
> On Thu, Jul 19, 2018 at 4:33 PM Andrea Giammarchi <
> andrea.giammarchi at gmail.com> wrote:
>
>> sorry, that'd be `public get resolve()` and also `public #resolve()` so
>> nobody should be confused about the fact I'm talking about public static
>> methods.
>>
>> On Thu, Jul 19, 2018 at 4:32 PM Andrea Giammarchi <
>> andrea.giammarchi at gmail.com> wrote:
>>
>>> I know it's about subclassing, which is why I've asked why, once there's
>>> no context, the default/base one is not considered, but since everyone came
>>> back with the subclassing issue, which is actually what I've said myself on
>>> twitter about the current state, how about changing all public static
>>> methods that need it, to be getters ?
>>>
>>> ```js
>>> class Promise {
>>>   #resolve(...args) {
>>>     return this.nativeImplementation(...args);
>>>   }
>>>   get resolve() {
>>>     return #resolve.bind(this);
>>>   }
>>> }
>>> ```
>>>
>>> we could argue `Promise.resolve === Promise.resolve` should be
>>> preserved, as behavior, so that we need a lazy defined getter ... **but**
>>> why not making public static restructuring from known constructors work
>>> regardless, under all circumstances ?
>>>
>>>
>>> On Thu, Jul 19, 2018 at 4:11 PM T.J. Crowder <
>>> tj.crowder at farsightsoftware.com> wrote:
>>>
>>>> On Thu, Jul 19, 2018 at 12:56 PM, Andrea Giammarchi
>>>> <andrea.giammarchi at gmail.com> wrote:
>>>> > Why cannot Promise methods fallback to Promise constructor when the
>>>> > class/context is not available?
>>>>
>>>> That sounds reasonable on first glance, but I'd be concerned about what
>>>> happens when you do it after subclassing:
>>>>
>>>> ```js
>>>> class MyPromise extends Promise {
>>>>     // ...and adds some important feature...
>>>> }
>>>> // ...
>>>> const {resolve, reject} = MyPromise;
>>>> const p = resolve();
>>>> p.someImportantFeature(/*...*/); // TypeError: undefined is not a
>>>> function
>>>> ```
>>>>
>>>> ...since `resolve` fell back to `Promise`. That feels like a footgun.
>>>> Either subclassers would have to handle that, which they will forget to do,
>>>> or it has to be a bit more complicated than just a simple fallback to `
>>>> Promise` (I don't immediately know what that "more complicated" answer
>>>> would be.)
>>>>
>>>> -- T.J. Crowder
>>>>
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