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Date: Thu, 6 Feb 2025 23:43:27 +1300
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Subject: Re: [PHP-DEV] Pattern matching details questions
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From: Weedpacket@varteg.nz (Morgan)

On 2025-02-04 17:31, Larry Garfield wrote:
> 
> 
> However, there is a concern that it wouldn't be self-evident to PHP devs, and the variable binding side should have the extra marker.  Ilija has suggested &, as that's what's used for references, which would result in:
> 
> $b = '12';
> 
> if ($arr is ['a' => &$a, 'b' => $b]) {
>      print $a;
> }
> 
> There are two concerns with this approach.
> 
> 1. The & could get confusing with an AND conjunction, eg, `$value is int & &$x` (which is how you would bind $value to $x iff it is an integer).
> 2. In practice, binding is almost certainly going to be vastly more common than pinning, so it should likely have the shorter syntax.
> 

There is already something analogous, in the sense of "binding to 
someone else's variable" in named parameters. Running with that analogy 
gives:

$b = '12';
  if ($arr is ['a' => a:, 'b' => $b]) {
       print $a;
  }