Nice use of generators! I'll save this one into my toolbox.
/#!/JoePea
On Mar 4, 2016 6:43 PM, "Jordan Harband" <[email protected]> wrote:
> While I would like a function for this too, this is pretty trivial:
>
> ```
> function* enumerate(obj) { for (var key in obj) { yield [key, obj[key]]; }
> }
>
> for (const [key, value] of enumerate(obj) {
> doStuff(key, value);
> }
> ```
>
> On Fri, Mar 4, 2016 at 1:08 PM, Edwin Reynoso <[email protected]> wrote:
>
>> Okay that makes sense, but the `Object.forIn` confused me, then that'd be
>> a bad name because then its not really looping like for-in
>>
>> On Fri, Mar 4, 2016 at 4:07 PM Logan Smyth <[email protected]> wrote:
>>
>>> Edwin, the original example loop explicitly checks
>>> `obj.hasOwnProperty(key)`,
>>> so properties in the prototype chain are not an issue here.
>>>
>>> On Fri, Mar 4, 2016 at 1:04 PM, Edwin Reynoso <[email protected]> wrote:
>>>
>>>> Sorry guys but this is very wrong, for in, loops through all properties
>>>> even the ones inherited from all prototypes, while Object.keys() and
>>>> Object.entries() do not. They are indeed very different
>>>>
>>>> On Fri, Mar 4, 2016 at 1:45 PM Langdon <[email protected]> wrote:
>>>>
>>>>> Ahhh, nothing. I never think about destructuring. Thanks!
>>>>>
>>>>> On Fri, Mar 4, 2016 at 1:41 PM, Caitlin Potter <[email protected]
>>>>> > wrote:
>>>>>
>>>>>> > Object.entries does look nice, but 2 arguments is more
>>>>>> straightforward than a passing around a pair.
>>>>>>
>>>>>> What’s the problem with `for (let [key, value] of
>>>>>> Object.entries(obj)) { …. }`
>>>>>>
>>>>>> > As well (and perhaps more importantly), temporarily building an
>>>>>> array of arrays so we can forEach it, seems way less efficient than forIn
>>>>>> is/would be.
>>>>>>
>>>>>> You might be surprised — If the pair never reaches geriatric status
>>>>>> (old generation/tenured space, etc), it could be allocated and cleaned up
>>>>>> relatively quickly.
>>>>>>
>>>>>> On Mar 4, 2016, at 1:28 PM, Langdon <[email protected]> wrote:
>>>>>>
>>>>>> My gripe with Object.keys is that it requires a closure to use
>>>>>> effectively.
>>>>>>
>>>>>> Object.entries does look nice, but 2 arguments is more
>>>>>> straightforward than a passing around a pair.
>>>>>>
>>>>>> As well (and perhaps more importantly), temporarily building an array
>>>>>> of arrays so we can forEach it, seems way less efficient than forIn
>>>>>> is/would be.
>>>>>>
>>>>>> On Fri, Mar 4, 2016 at 1:20 PM, Isiah Meadows <[email protected]
>>>>>> > wrote:
>>>>>>
>>>>>>> Yeah, and those effectively nullify this, anyways.
>>>>>>>
>>>>>>> On Fri, Mar 4, 2016, 12:55 Simon Blackwell <
>>>>>>> [email protected]> wrote:
>>>>>>>
>>>>>>>> Not sure of the rationale; however, it looks like Chrome now
>>>>>>>> supports something similar natively:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> https://twitter.com/malyw/status/704972953029623808?utm_source=javascriptweekly&utm_medium=email
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> *From:* es-discuss [mailto:[email protected]] *On
>>>>>>>> Behalf Of *Langdon
>>>>>>>> *Sent:* Friday, March 4, 2016 11:22 AM
>>>>>>>> *To:* [email protected]
>>>>>>>> *Subject:* Object.prototype.forIn
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> My apologies if this has been discussed before (I have to imagine
>>>>>>>> it has, but couldn't find anything).
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Why isn't there a `forIn` method on Object natively?
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Something that simply wraps this all-to-common code:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> var key;
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> for (key in obj) {
>>>>>>>>
>>>>>>>> if (obj.hasOwnProperty(key) === true) {
>>>>>>>>
>>>>>>>> ...
>>>>>>>>
>>>>>>>> }
>>>>>>>>
>>>>>>>> }
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Example: https://jsfiddle.net/langdonx/d4Lph13u/
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> TIA,
>>>>>>>>
>>>>>>>> Langdon
>>>>>>>> _______________________________________________
>>>>>>>> es-discuss mailing list
>>>>>>>> [email protected]
>>>>>>>> https://mail.mozilla.org/listinfo/es-discuss
>>>>>>>>
>>>>>>>
>>>>>> _______________________________________________
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>>>>>>
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>> es-discuss mailing list
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>>>>> https://mail.mozilla.org/listinfo/es-discuss
>>>>>
>>>> --
>>>> Thanks
>>>> - Edwin
>>>>
>>>> _______________________________________________
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>>>> https://mail.mozilla.org/listinfo/es-discuss
>>>>
>>>>
>>> --
>> Thanks
>> - Edwin
>>
>> _______________________________________________
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>>
>
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