Object.clone - not quite a proposal

Andrea Giammarchi andrea.giammarchi at gmail.com
Fri Sep 25 00:32:39 UTC 2015


Also, one reason I haven't used that, if you clone descriptors you do a
shallow copy, not a deep one ;-)

On Fri, Sep 25, 2015 at 2:31 AM, Andrea Giammarchi <
andrea.giammarchi at gmail.com> wrote:

> Claude, you know that's actually *my* proposal, right? :P
> https://gist.github.com/WebReflection/9353781
>
> But yeah, that's the spirit!
>
> On Thu, Sep 24, 2015 at 8:21 PM, Claude Pache <claude.pache at gmail.com>
> wrote:
>
>>
>> Le 24 sept. 2015 à 19:58, Andrea Giammarchi <andrea.giammarchi at gmail.com>
>> a écrit :
>>
>> Last, but not least, one does not simply assign properties in JavaScript.
>> If you want to clone you don't want to miss possible get/set accessors in
>> the process, you don't want to miss getOwnPropertyNames and
>> getOwnpropertySymbols neither, so the last loop doesn't work as proposal.
>>
>> ```js
>> // simplified version for regular objects only
>> // basically just the correct substitute of your last temp logic
>> Object.clone = function (src) {
>>   return Object.setPrototypeOf(
>>     Reflect.ownKeys(src).reduce((o, k) => {
>>       var d = Object.getOwnPropertyDescriptor(src, k);
>>       if (
>>         o.hasOwnProperty.call(d, 'value') &&
>>         /function|object/.test(typeof d.value)
>>       ) d.value = Object.clone(d.value);
>>       return Object.defineProperty(o, k, d);
>>     }, {}),
>>     Object.getPrototypeOf(src)
>>   );
>> };
>> ```
>>
>>
>> ```js
>> Object.clone = function (src) {
>>     return Object.create(Object.getPrototypeOf(src),
>> Object.getOwnPropertyDescriptors(src))
>> }
>> ```
>>
>> where  the definition of `Object.getOwnPropertyDescriptors()` is left as
>> an exercise to the reader.
>>
>>
>> —Claude
>>
>>
>
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