Re: Any chance for an `Object.assignProperties` ?
Anyway, if anyone is interested, I've published the `assign-properties`
module [1]
[1] https://github.com/WebReflection/assign-properties#readme
On Thu, Feb 13, 2020 at 7:51 PM Andrea Giammarchi <
andrea.giammar...@gmail.com> wrote:
> The fact `assign` doesn't copy descriptors and has potential side-effects
> is documented extensively though, meaning there is room for improvement, or
> simply a missing native way to do that, like it was for
> `getOwnPropertyDescriptors`, that following your logic should've never
> landed.
>
> But I guess I'd go with the usual "yet another micro library" approach
> instead, so that at least I won't have to deal with assign shenanigans when
> I mean to copy accessors too.
>
> On Thu, Feb 13, 2020 at 7:33 PM Jordan Harband wrote:
>
>> It seems like it’s the exact implementation you want, just for 1 object
>> instead of N.
>>
>> Object.assign was added because versions of it were all over the web,
>> used very frequently. How frequent is the pattern where people want to copy
>> descriptors, such that it would deserve reification in the language?
>>
>> On Thu, Feb 13, 2020 at 10:23 AM Andrea Giammarchi <
>> andrea.giammar...@gmail.com> wrote:
>>
>>> That has nothing to do with this, right?
>>>
>>> ```js
>>> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
>>> const assignProperties = (base, ...mixins) => defineProperties(
>>> base,
>>> mixins.reduce(
>>> (descriptors, mixin) => assign(
>>> descriptors,
>>> getOwnPropertyDescriptors(mixin)
>>> ),
>>> {}
>>> )
>>> );
>>> ```
>>>
>>> On Thu, Feb 13, 2020 at 6:51 PM Jordan Harband wrote:
>>>
`Object.defineProperties(target,
Object.getOwnPropertyDescriptors(source))`?
On Thu, Feb 13, 2020 at 2:24 AM Andrea Giammarchi <
andrea.giammar...@gmail.com> wrote:
> Both `Object.assign` and `{...extend}` suffer a tiny gotcha:
> properties are never assigned, neither retrieved, as accessors, with
> side-effects too.
>
> Example:
> ```js
> const Counter = {
> _count: 0,
> get count() {
> return this._count++;
> }
> };
>
> const incr1 = Object.assign({}, Counter);
> const incr2 = {...Counter};
>
> console.log(
> incr1.count,// 0
> incr2.count,// 1
> Counter._count // 2
> );
>
> // functionality also compromised
> console.log(incr1.count === incr1.count);
> ```
>
> Not only most of the time this is unexpected, but there's literally no
> way to pass along accessors with a similar `Object.assign` ease, even if
> that's what most developers would expect (at least up to the first time
> they encounter above issue).
>
> How about we introduce `Object.assignProperties` instead?
>
> A polyfill example:
>
> ```js
> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
> const assignProperties = (base, ...mixins) => defineProperties(
> base,
> mixins.reduce(
> (descriptors, mixin) => assign(
> descriptors,
> getOwnPropertyDescriptors(mixin)
> ),
> {}
> )
> );
> ```
>
> We can now use objects and mixins without side-effecting sources used
> to extend, and preserving accessors in the process.
>
> ```js
> const Counter = {
> _count: 0,
> get count() {
> return this._count++;
> }
> };
>
> const incr1 = Object.assignProperties({}, Counter);
> const incr2 = Object.assignProperties({}, Counter);
>
> console.log(
> incr1.count,// 0
> incr2.count,// 0
> Counter._count // 0
> );
>
> // always false: preserved functionality
> console.log(incr1.count === incr1.count);
> ```
>
> Thoughts ?
> ___
> es-discuss mailing list
> es-discuss@mozilla.org
> https://mail.mozilla.org/listinfo/es-discuss
>
___
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https://mail.mozilla.org/listinfo/es-discuss
Re: Any chance for an `Object.assignProperties` ?
The fact `assign` doesn't copy descriptors and has potential side-effects
is documented extensively though, meaning there is room for improvement, or
simply a missing native way to do that, like it was for
`getOwnPropertyDescriptors`, that following your logic should've never
landed.
But I guess I'd go with the usual "yet another micro library" approach
instead, so that at least I won't have to deal with assign shenanigans when
I mean to copy accessors too.
On Thu, Feb 13, 2020 at 7:33 PM Jordan Harband wrote:
> It seems like it’s the exact implementation you want, just for 1 object
> instead of N.
>
> Object.assign was added because versions of it were all over the web, used
> very frequently. How frequent is the pattern where people want to copy
> descriptors, such that it would deserve reification in the language?
>
> On Thu, Feb 13, 2020 at 10:23 AM Andrea Giammarchi <
> andrea.giammar...@gmail.com> wrote:
>
>> That has nothing to do with this, right?
>>
>> ```js
>> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
>> const assignProperties = (base, ...mixins) => defineProperties(
>> base,
>> mixins.reduce(
>> (descriptors, mixin) => assign(
>> descriptors,
>> getOwnPropertyDescriptors(mixin)
>> ),
>> {}
>> )
>> );
>> ```
>>
>> On Thu, Feb 13, 2020 at 6:51 PM Jordan Harband wrote:
>>
>>> `Object.defineProperties(target,
>>> Object.getOwnPropertyDescriptors(source))`?
>>>
>>> On Thu, Feb 13, 2020 at 2:24 AM Andrea Giammarchi <
>>> andrea.giammar...@gmail.com> wrote:
>>>
Both `Object.assign` and `{...extend}` suffer a tiny gotcha: properties
are never assigned, neither retrieved, as accessors, with side-effects too.
Example:
```js
const Counter = {
_count: 0,
get count() {
return this._count++;
}
};
const incr1 = Object.assign({}, Counter);
const incr2 = {...Counter};
console.log(
incr1.count,// 0
incr2.count,// 1
Counter._count // 2
);
// functionality also compromised
console.log(incr1.count === incr1.count);
```
Not only most of the time this is unexpected, but there's literally no
way to pass along accessors with a similar `Object.assign` ease, even if
that's what most developers would expect (at least up to the first time
they encounter above issue).
How about we introduce `Object.assignProperties` instead?
A polyfill example:
```js
const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
const assignProperties = (base, ...mixins) => defineProperties(
base,
mixins.reduce(
(descriptors, mixin) => assign(
descriptors,
getOwnPropertyDescriptors(mixin)
),
{}
)
);
```
We can now use objects and mixins without side-effecting sources used
to extend, and preserving accessors in the process.
```js
const Counter = {
_count: 0,
get count() {
return this._count++;
}
};
const incr1 = Object.assignProperties({}, Counter);
const incr2 = Object.assignProperties({}, Counter);
console.log(
incr1.count,// 0
incr2.count,// 0
Counter._count // 0
);
// always false: preserved functionality
console.log(incr1.count === incr1.count);
```
Thoughts ?
___
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
>>>
___
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
Re: Any chance for an `Object.assignProperties` ?
It seems like it’s the exact implementation you want, just for 1 object
instead of N.
Object.assign was added because versions of it were all over the web, used
very frequently. How frequent is the pattern where people want to copy
descriptors, such that it would deserve reification in the language?
On Thu, Feb 13, 2020 at 10:23 AM Andrea Giammarchi <
andrea.giammar...@gmail.com> wrote:
> That has nothing to do with this, right?
>
> ```js
> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
> const assignProperties = (base, ...mixins) => defineProperties(
> base,
> mixins.reduce(
> (descriptors, mixin) => assign(
> descriptors,
> getOwnPropertyDescriptors(mixin)
> ),
> {}
> )
> );
> ```
>
> On Thu, Feb 13, 2020 at 6:51 PM Jordan Harband wrote:
>
>> `Object.defineProperties(target,
>> Object.getOwnPropertyDescriptors(source))`?
>>
>> On Thu, Feb 13, 2020 at 2:24 AM Andrea Giammarchi <
>> andrea.giammar...@gmail.com> wrote:
>>
>>> Both `Object.assign` and `{...extend}` suffer a tiny gotcha: properties
>>> are never assigned, neither retrieved, as accessors, with side-effects too.
>>>
>>> Example:
>>> ```js
>>> const Counter = {
>>> _count: 0,
>>> get count() {
>>> return this._count++;
>>> }
>>> };
>>>
>>> const incr1 = Object.assign({}, Counter);
>>> const incr2 = {...Counter};
>>>
>>> console.log(
>>> incr1.count,// 0
>>> incr2.count,// 1
>>> Counter._count // 2
>>> );
>>>
>>> // functionality also compromised
>>> console.log(incr1.count === incr1.count);
>>> ```
>>>
>>> Not only most of the time this is unexpected, but there's literally no
>>> way to pass along accessors with a similar `Object.assign` ease, even if
>>> that's what most developers would expect (at least up to the first time
>>> they encounter above issue).
>>>
>>> How about we introduce `Object.assignProperties` instead?
>>>
>>> A polyfill example:
>>>
>>> ```js
>>> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
>>> const assignProperties = (base, ...mixins) => defineProperties(
>>> base,
>>> mixins.reduce(
>>> (descriptors, mixin) => assign(
>>> descriptors,
>>> getOwnPropertyDescriptors(mixin)
>>> ),
>>> {}
>>> )
>>> );
>>> ```
>>>
>>> We can now use objects and mixins without side-effecting sources used to
>>> extend, and preserving accessors in the process.
>>>
>>> ```js
>>> const Counter = {
>>> _count: 0,
>>> get count() {
>>> return this._count++;
>>> }
>>> };
>>>
>>> const incr1 = Object.assignProperties({}, Counter);
>>> const incr2 = Object.assignProperties({}, Counter);
>>>
>>> console.log(
>>> incr1.count,// 0
>>> incr2.count,// 0
>>> Counter._count // 0
>>> );
>>>
>>> // always false: preserved functionality
>>> console.log(incr1.count === incr1.count);
>>> ```
>>>
>>> Thoughts ?
>>> ___
>>> es-discuss mailing list
>>> es-discuss@mozilla.org
>>> https://mail.mozilla.org/listinfo/es-discuss
>>>
>>
___
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
Re: Any chance for an `Object.assignProperties` ?
That has nothing to do with this, right?
```js
const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
const assignProperties = (base, ...mixins) => defineProperties(
base,
mixins.reduce(
(descriptors, mixin) => assign(
descriptors,
getOwnPropertyDescriptors(mixin)
),
{}
)
);
```
On Thu, Feb 13, 2020 at 6:51 PM Jordan Harband wrote:
> `Object.defineProperties(target,
> Object.getOwnPropertyDescriptors(source))`?
>
> On Thu, Feb 13, 2020 at 2:24 AM Andrea Giammarchi <
> andrea.giammar...@gmail.com> wrote:
>
>> Both `Object.assign` and `{...extend}` suffer a tiny gotcha: properties
>> are never assigned, neither retrieved, as accessors, with side-effects too.
>>
>> Example:
>> ```js
>> const Counter = {
>> _count: 0,
>> get count() {
>> return this._count++;
>> }
>> };
>>
>> const incr1 = Object.assign({}, Counter);
>> const incr2 = {...Counter};
>>
>> console.log(
>> incr1.count,// 0
>> incr2.count,// 1
>> Counter._count // 2
>> );
>>
>> // functionality also compromised
>> console.log(incr1.count === incr1.count);
>> ```
>>
>> Not only most of the time this is unexpected, but there's literally no
>> way to pass along accessors with a similar `Object.assign` ease, even if
>> that's what most developers would expect (at least up to the first time
>> they encounter above issue).
>>
>> How about we introduce `Object.assignProperties` instead?
>>
>> A polyfill example:
>>
>> ```js
>> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
>> const assignProperties = (base, ...mixins) => defineProperties(
>> base,
>> mixins.reduce(
>> (descriptors, mixin) => assign(
>> descriptors,
>> getOwnPropertyDescriptors(mixin)
>> ),
>> {}
>> )
>> );
>> ```
>>
>> We can now use objects and mixins without side-effecting sources used to
>> extend, and preserving accessors in the process.
>>
>> ```js
>> const Counter = {
>> _count: 0,
>> get count() {
>> return this._count++;
>> }
>> };
>>
>> const incr1 = Object.assignProperties({}, Counter);
>> const incr2 = Object.assignProperties({}, Counter);
>>
>> console.log(
>> incr1.count,// 0
>> incr2.count,// 0
>> Counter._count // 0
>> );
>>
>> // always false: preserved functionality
>> console.log(incr1.count === incr1.count);
>> ```
>>
>> Thoughts ?
>> ___
>> es-discuss mailing list
>> es-discuss@mozilla.org
>> https://mail.mozilla.org/listinfo/es-discuss
>>
>
___
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
Re: Any chance for an `Object.assignProperties` ?
`Object.defineProperties(target, Object.getOwnPropertyDescriptors(source))`?
On Thu, Feb 13, 2020 at 2:24 AM Andrea Giammarchi <
andrea.giammar...@gmail.com> wrote:
> Both `Object.assign` and `{...extend}` suffer a tiny gotcha: properties
> are never assigned, neither retrieved, as accessors, with side-effects too.
>
> Example:
> ```js
> const Counter = {
> _count: 0,
> get count() {
> return this._count++;
> }
> };
>
> const incr1 = Object.assign({}, Counter);
> const incr2 = {...Counter};
>
> console.log(
> incr1.count,// 0
> incr2.count,// 1
> Counter._count // 2
> );
>
> // functionality also compromised
> console.log(incr1.count === incr1.count);
> ```
>
> Not only most of the time this is unexpected, but there's literally no way
> to pass along accessors with a similar `Object.assign` ease, even if that's
> what most developers would expect (at least up to the first time they
> encounter above issue).
>
> How about we introduce `Object.assignProperties` instead?
>
> A polyfill example:
>
> ```js
> const {assign, defineProperties, getOwnPropertyDescriptors} = Object;
> const assignProperties = (base, ...mixins) => defineProperties(
> base,
> mixins.reduce(
> (descriptors, mixin) => assign(
> descriptors,
> getOwnPropertyDescriptors(mixin)
> ),
> {}
> )
> );
> ```
>
> We can now use objects and mixins without side-effecting sources used to
> extend, and preserving accessors in the process.
>
> ```js
> const Counter = {
> _count: 0,
> get count() {
> return this._count++;
> }
> };
>
> const incr1 = Object.assignProperties({}, Counter);
> const incr2 = Object.assignProperties({}, Counter);
>
> console.log(
> incr1.count,// 0
> incr2.count,// 0
> Counter._count // 0
> );
>
> // always false: preserved functionality
> console.log(incr1.count === incr1.count);
> ```
>
> Thoughts ?
> ___
> es-discuss mailing list
> es-discuss@mozilla.org
> https://mail.mozilla.org/listinfo/es-discuss
>
___
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
