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Re: Not understanding "sort" with an argument

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John G Harris <niam@jghnorth.org.uk.invalid> wrote on 14 Aug 2018 in 
comp.lang.javascript:

> On Tue, 14 Aug 2018 11:25:53 -0700 (PDT), bit-naughty@hotmail.com
> wrote:
> 
>>On Friday, August 10, 2018 at 2:17:08 PM UTC+5:30, John G Harris wrote:
>>> 
>>> The function comparePerson has been given to friends.sort, which uses
>>> it to help it do the sorting.
>>
>>"help" it *how*?
> 
> Well, when you want to sort things into order you have to be able to
> tell whether this thing is before or after that thing. That's what the
> comparePerson function does. The sort function does many of these
> comparisons in order to do its job of making earlier things come
> before later things. 

Not so.

In an array, and this is about sorting an array [or a string posing as an 
array of letters] there is no "earlier" and "later", just difference in 
element position number.
 
> That's the help the compare function gives to the sort function.

No.

The compare function is not just a helper, it defines the algoritm that acts 
as the "worker" of the sort, determining in every internal sorting-step if 
two adjacent elements need to be toggled or not. The sort therefore listens 
to which of the three values the compare returns, *1, 0 or +1 for less than, 
equal end more than.

Such a sort might be alphabetical, numerical, or much more compound.
 
> You might like to read up on sort algorithms, but beware, the more
> efficient the algorithm the more compicated the code :-(

Nonsense, methinks.
What gives you that idea?

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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Not understanding "sort" with an argument bit-naughty@hotmail.com - 2018-08-10 01:11 -0700
  Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-10 09:47 +0100
    Re: Not understanding "sort" with an argument bit-naughty@hotmail.com - 2018-08-14 11:25 -0700
      Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-14 20:04 +0100
        Re: Not understanding "sort" with an argument "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2018-08-14 23:00 +0200
          Re: Not understanding "sort" with an argument "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2018-08-14 23:02 +0200
          Re: Not understanding "sort" with an argument Julio Di Egidio <julio@diegidio.name> - 2018-08-15 04:20 -0700
          Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-15 19:15 +0100
            Re: Not understanding "sort" with an argument "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2018-08-15 21:56 +0200
              Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-16 15:24 +0100
                Re: Not understanding "sort" with an argument Julio Di Egidio <julio@diegidio.name> - 2018-08-16 07:51 -0700
                Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-16 18:51 +0100
                Re: Not understanding "sort" with an argument Julio Di Egidio <julio@diegidio.name> - 2018-08-16 11:21 -0700
                Re: Not understanding "sort" with an argument John G Harris <niam@jghnorth.org.uk.invalid> - 2018-08-17 10:44 +0100
  Re: Not understanding "sort" with an argument Julio Di Egidio <julio@diegidio.name> - 2018-08-15 03:58 -0700

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