Re: Faster procedure then shift to remove first element of list or array?

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From	Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups	comp.lang.javascript
Subject	Re: Faster procedure then shift to remove first element of list or array?
Date	Fri, 19 Mar 2021 02:59:17 +0100
Organization	PointedEars Software (PES)
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Michael Haufe (TNO) wrote:

> On Thursday, March 18, 2021 at 6:26:14 AM UTC-5, Thomas 'PointedEars' Lahn
> wrote:
>> Array.prototype.shift() usually is not available for non-Array instances;
>> so in order to use .shift(), it may be necessary to convert the non-Array
>> to Array, or treat it as such (by Function.prototype.call()/.apply()),
>> which can be expensive.
> 
> "The shift function is intentionally generic; it does not require that its
> this value be an Array object. Therefore it can be transferred to other
> kinds of objects for use as a method."
> <https://tc39.es/ecma262/#sec-array.prototype.shift>

That is precisely what I said.
 
> How expensive is call/apply really? […]

Calling .call()/.apply() is one aspect, but I was also considering the cost 
of accessing the data and moving it around.  Think about the example of 
.slice() vs. direct access that we discussed earlier.

-- 
PointedEars
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<https://github.com/PointedEars> | <http://PointedEars.de/wsvn/>
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Thread

Faster procedure then shift to remove first element of list or array? Jonas Thörnvall <jonas.thornvall@gmail.com> - 2021-03-16 22:51 -0700
  Re: Faster procedure then shift to remove first element of list or array? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-17 06:09 -0700
    Re: Faster procedure then shift to remove first element of list or array? Jonas Thörnvall <jonas.thornvall@gmail.com> - 2021-03-17 06:45 -0700
    Re: Faster procedure then shift to remove first element of list or array? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-18 12:26 +0100
      Re: Faster procedure then shift to remove first element of list or array? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-18 06:30 -0700
        Re: Faster procedure then shift to remove first element of list or array? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-19 02:59 +0100
        Re: Faster procedure then shift to remove first element of list or array? Jonas Thörnvall <jonas.thornvall@gmail.com> - 2021-03-19 12:39 -0700
          Re: Faster procedure then shift to remove first element of list or array? "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-19 13:55 -0700
          Re: Faster procedure then shift to remove first element of list or array? "sc...@sauyet.com" <scott@sauyet.com> - 2021-03-19 14:42 -0700

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