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Date: Sat, 25 Oct 2025 11:15:28 +1300
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Subject: Re: [PHP-DEV] RFC proposal for adding SORT_STRICT flag to
 array_unique()
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From: Weedpacket@varteg.nz (Morgan)

On 2025-10-25 08:34, Jason Marble wrote:
> Hello everybody!
> 
> 
> The potential for a `SORT_NATURAL` flag also came to mind as another 
> useful addition, but I believe `SORT_STRICT` is the more critical 
> feature to discuss first.
> 

I know I find array_unique generally useless due to its insistence on 
stringifying everything for comparison.

```
$uniques = [];
foreach($source_array as $a) {
     if(!in_array($a, $uniques, true)) {
         $uniques[] = $a;
     }
}
```

I seem to recall part of the issue is that array_unique works by sorting 
its elements so that "equal" values are adjacent. I know this would be 
done on O(n log(n)) vs. O(n^2) grounds, but that could be addressed at 
least in part by a smarter sort criterion that sorts by type/class (in 
some arbitrary order) before sorting by value. For uncomparable types 
(i.e., instances of most classes) this would be by object ID, because we 
don't _actually_ care about ordering.