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Date: Tue, 25 Mar 2025 05:53:30 +0000
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Subject: Re: [PHP-DEV] Feedback for nullc Idea
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From: php@miqrogroove.com (Robert Chapin)

On 3/23/2025 11:10 AM, Larry Garfield wrote:
> I'm not sure it justifies a new pseudo-function language construct.

Fair enough.  Thank you for the feedback.

On 3/23/2025 2:37 PM, Rowan Tommins [IMSoP] wrote:
> It's telling that all your examples with ?? put a value other than 
> null on the right-hand side.

I may have over-simplified the examples.  Comparing $input === 'yes' 
will have the same result whether $input is null or 'none' or an empty 
string.  So not implying a result type, just want to compare a literal 
or other variable to $input even when not declared.

A different example could be if (coalesce($_POST['tick']) > 10) return;

> In my experience, a lot of people struggle to follow logic like this, 
> and it can easily lead to subtle bugs. Compare the same logic with 
> explicit defaults:
>
> if (nullc($test, 'off') === 'on')
> if (nullc($test, 'on') !== 'off')

Having optional defaults seems fine.  Meanwhile...

if ($test ?? 'on' !== 'on') will evaluate to true when $test is set to 'on'.

> There is a small risk that some people might have an existing function 
> with different behaviour, e.g. a test on "emptiness" with `$arg != 
> false`, and need to rename it when upgrading PHP.

This is a good point.  I assume that risk exists for all new functions 
and needs to be considered.

> I'm still only lukewarm on including it, because it's mostly just 
> reminding you to include a pair of parentheses:

Think of it as a quick way to use an undeclared variable without having 
to explain operator precedence to other developers.

In any case, thank you for the feedback.