> On Oct 14, 2023, at 16:30, Nikita Popov <nikita....@gmail.com> wrote:
> 
> On Sat, Oct 14, 2023, at 20:00, David Grudl wrote:
>> PHP lacks two very basic functions for working with arrays:
>> 
>> - array_first() returning the first element of an array (or null)
>> - array_last() returning the last element of the array (or null)
>> 
>> While PHP has functions that return the first and last keys,
>> array_key_first() and array_key_last(), it does not have more useful
>> functions for values.
>> 
>> a) What about reset() and end()?
>> Programmers "abuse" the reset() and end() functions for this purpose.
>> The problem is that these functions are used to move the internal
>> pointer in the array. Which is why they have a name that is
>> inappropriate when used in the sense of "return me the first element".
>> 
>> Much worse, they shouldn't to be used to get first/last value, because
>> they have a side effect (i.e. moving the pointer).
>> 
>> Further, in the absence of an element, they return the obsolete false
>> and not the currently expected null, which can be combined with the ??
>> operator. In this they differ from the similar functions
>> array_key_first() and array_key_last().
>> 
>> b) What about $array[array_key_first($array)]?
>> 
>> For such basic functions as returning the first and last item in an
>> array, there should be a function in the basic package, not a
>> workaround. Moreover, this requires having the array in a local
>> variable, since $this->getFoo()[array_key_first($this->getFoo())]
>> would be very inefficient and possibly incorrect.
>> 
>> c) Two such functions were proposed and rejected during the
>> array_key_first/last RFC
>> (https://wiki.php.net/rfc/array_key_first_last)
>> 
>> Yes, that was in 2018. At that time, functions like str_contains() or
>> str_starts_with() wouldn't have even come into existence, just because
>> there was an obscure way to do it without them. I believe we've moved
>> on since then. Today we know how useful it is to use simple,
>> easy-to-understand methods, both for programmers who write and read
>> the code.
>> 
>> DG
> 
> I'm in favor of adding these.
> 
> To add to what you already said, because reset/end modify the array, there's 
> a good chance that calling these functions will copy the whole array due to a 
> modification you are not actually interested in.
> 
> So basically you have the choice between calling end(), which is the wrong 
> thing to do semantically and may be slow, or using 
> $array[array_key_last($array)], which is rather convoluted, and incorrect if 
> the array is potentially empty.
> 
> Regards,
> Nikita

I’m in favor of these functions, for all the same aforementioned reasons.

Cheers,
Ben

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