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Date: Thu, 22 Mar 2018 14:45:31 +0100
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Subject: Re: [PHP-DEV] [RFC] [DISCUSSION] Improve null-coalescing operator
 (??) adding empty check (??:)
From: info@eordes.com (Lito)

This is a RFC karma request for my wiki account.

I want to create a RFC with my proposal: Improve null-coalescing 
operator (??) adding empty check (??:)

First list message is: http://news.php.net/php.internals/101606

The main idea is simplify "empty" check on non existing keys or object 
attributes. Same as "?:" but also checking undefined.

Current check:

$value = empty($user->thisOptionalAttributeCanBeEmptyOrNotExists) ? 
'without value' : $user->thisOptionalAttributeCanBeEmptyOrNotExists;

New feature:

$value = $user->thisOptionalAttributeCanBeEmptyOrNotExists ??: 'without 
value';

I think that could be very usefull on inline "exists" + "not empty" 
checks with a more clear code.

It's possible?

Thanks,
Lito.

On 17/01/18 19:47, Lito wrote:
> On 17/01/18 19:43, Andrey Andreev wrote:
>> Hi,
>>
>>
>> On Wed, Jan 17, 2018 at 8:28 PM, Lito <info@eordes.com> wrote:
>>> No $foo ?: 'default' , it's only equivalent to (isset($foo) && $foo) 
>>> ? $foo
>>> : 'default' if $foo exists.
>>>
>>> Also PHP has added ?? as null-coalescing operator that works with 
>>> undefined
>>> variables/attributes/keys, my proposal is an improvement over this one.
>>>
>>> I don't want to endorse usage of undefined variables, can be used in 
>>> a large
>>> set of situations, like object attributes, array keys, etc...
>>>
>>> Anyway thanks for your feedback.
>>> Lito.
>>>
>> There is a shorter version:
>>
>>      empty($foo) ? 'default' : $foo;
>>
>> And I think that's quite convenient for the few use cases it has
>> (refer to Nikita's reply).
>>
>> Cheers,
>> Andrey.
>>
> Yes, I think that:
>
> $foo = $foo ??: 'default';
>
> Is more clear and with less code than:
>
> $foo = empty($foo) ? 'default' : $foo;
>
> As ?? does.
>
> Regards,
> Lito.
>
>