Can't do push in forEach

Thu May 14 19:14:25 UTC 2015

Yes I was thinking that too. But if it just default to binding to the object on which the method is being call on it self since this is technically an partial application function.

Or it can have a forth optional parameters to allow what object should be this. Or can simple just use bind call or apply method.

Sent from my iPhone

> On May 14, 2015, at 3:07 PM, Jordan Harband <ljharb at gmail.com> wrote:
> 
> `arr.push` is `Array.prototype.push`. If you want it bound to `arr`, you'd need to use `.bind` or actually call it with `arr.push()`. `arr.push.only` would lose the context of the "arr", so that's not an option for your use case as described.
> 
> Arrow functions (with Array#map perhaps?) are your best bet here.
> 
>> On Thu, May 14, 2015 at 11:50 AM, Andrea Giammarchi <andrea.giammarchi at gmail.com> wrote:
>> > So this style I favorite since I want to avoid creating another function:
>> 
>> this is like believing that `fn.bind()` won't create a different object/function ... right?
>> 
>> Or you want to lock that function to receive one forever until you unlock it? That's the only way you could mutate the function behavior without creating a new object/function like bind would do.
>> 
>> And since bind is at least 3X slower than fat arrow, why would you do that?
>> 
>> 
>>> On Thu, May 14, 2015 at 7:36 PM, Emanuel Allen <emanuelallen at hotmail.com> wrote:
>>> It should allow for:
>>> 
>>> arr.forEach(arr.push.only(1));//only return a function limiting the number of arguments pass to it...
>>> 
>>> But I guess this work too:
>>> arr.forEach(e=>arr.push(e));
>>> 
>>> But my goal was to just:
>>> arr.forEach(arr.push);//will not work
>>> 
>>> So this style I favorite since I want to avoid creating another function:
>>> arr.forEach(arr.push.only(1));
>>> 
>>> Even know only will return another function base on the parameter to you pass to it.
>>> 
>>> Still, I think it would be a great addition to the Function.prototype object.
>>> 
>>> JS4L
>>> 
>>>> On May 14, 2015, at 1:42 PM, Andrea Giammarchi <andrea.giammarchi at gmail.com> wrote:
>>>> 
>>>> `$1 => a.push($1)`
>>>> 
>>>> fat arrow function shines mostly in these cases, not sure there's a need for anything else.
>>>> 
>>>> `($1, $2, $3) => a.push($2, $3)`
>>>> 
>>>> Regards
>>>> 
>>>>> On Thu, May 14, 2015 at 5:26 PM, Emanuel Allen <emanuelallen at hotmail.com> wrote:
>>>>> That would be great to have an only method on Function.prototype.only
>>>>> 
>>>>> It can take one to three parameters as arguments:
>>>>> -Only with using the first argument:
>>>>> 
>>>>> SomeFunction.only(1);
>>>>> only allow the first argument in. It target the place holder so: fn.only(2) allow the two most left argument in.
>>>>> 
>>>>> -Only with using the first 2 argument:
>>>>> 
>>>>> SomeFunction.only(1,2);
>>>>> only allow the second argument in; the second argument target where to start and the first not how many to let in. So fn.only(2,3); let the third and fourth argument in. 
>>>>> 
>>>>> -Only with using all arguments placeholder:
>>>>> 
>>>>> SomeFunction.only(1,2,true);
>>>>> This will denote that we start from the right and and let the second from last argument in 
>>>>> 
>>>>> The last parameter is informing if we should start left or right when choosing the parameters to let in. The default is false; start left to right 
>>>>> 
>>>>> Internally this could use the function's arguments object to query what to let in.
>>>>> 
>>>>> JS4L
>>>>> 
>>>>>> On May 14, 2015, at 11:37 AM, Allen Wirfs-Brock <allen at wirfs-brock.com> wrote:
>>>>>> 
>>>>>> 
>>>>>>> On May 14, 2015, at 8:19 AM, Emanuel Allen wrote:
>>>>>>> 
>>>>>>> Oh yes that is correct since push will push in elements separated by commas... Still my original problem is that I can't simply do arr.push(arr2.push); but it doesn't matter since it'll also push the three parameters into the array as well. 
>>>>>> 
>>>>>> exactly, see http://www.wirfs-brock.com/allen/posts/166 
>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> Sent from my iPhone
>>>>>>> 
>>>>>>>> On May 14, 2015, at 10:49 AM, Erik Arvidsson <erik.arvidsson at gmail.com> wrote:
>>>>>>>> 
>>>>>>>> Still, the callback for forEach is called with 3 arguments; value, index and the array.
>>>>>>>> 
>>>>>>>> This is clearly documented in the spec and mdn and other resources.
>>>>>>>> 
>>>>>>>> 
>>>>>>>>> On Thu, May 14, 2015, 10:42 Garrett Smith <dhtmlkitchen at gmail.com> wrote:
>>>>>>>>> On 5/14/15, Emanuel Allen <emanuelallen at hotmail.com> wrote:
>>>>>>>>> > Surprise that I can't do arr1.forEeach(arr2.push);
>>>>>>>>> >
>>>>>>>>> 
>>>>>>>>> Check that line more carefully.
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>> > Will throw an error.
>>>>>>>>> >
>>>>>>>>> > Using bind as:
>>>>>>>>> >
>>>>>>>>> > push = arr2.bind(push);
>>>>>>>>> 
>>>>>>>>> Arrays don't have a bind method.
>>>>>>>>> --
>>>>>>>>> Garrett
>>>>>>>>> @xkit
>>>>>>>>> ChordCycles.com
>>>>>>>>> garretts.github.io
>>>>>>>>> personx.tumblr.com
>>>>>>>>> _______________________________________________
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>> 
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