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Date: Thu, 1 Jun 2023 18:02:18 +0200
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Subject: Proposal: addition of array_find() and array_find_key() functions
From: janusz@fide.pl (Janusz Szczypka)

Dear PHP Internals,

I would like to propose new functions to search in arrays: array_find() and
array_find_key().

array_find(): This function would allow developers to find the first 
element in
an array that satisfies a specific condition. The condition would be 
defined by
a callback function. The functionality would be similar to the existing
array_filter() function but would instead return the first element that 
matches
the callback condition, rather than all matching elements.
This function can be used in a way simliar to in_array with added 
functionality
of custom check.

array_find_key(): This function would return the key of the first 
element in an
array that matches a given condition, defined by a callback function. This
function can be used in a way simliar to array_search with added 
functionality
of custom check.

Both functions stop processing after first match is found, so any side 
effects
of the callbacks should be avoided.

Here are the proposed function definitions:

/**
  * @param callable(mixed):bool $callback
  */
function array_find(callable $callback, array $array)
{
     foreach ($array as $row) {
         if (call_user_func($callback, $row) === true) {
             return $row;
         }
     }
     return null;
}

/**
  * @param callable(mixed):bool $callback
  * @return null|int|string
  */
function array_find_key(callable $callback, array $array)
{
     foreach($array as $key => $row) {
         if (call_user_func($callback, $row) === true) {
             return $key;
         }
     }
     return null;
}

Both functions are easy to implement in PHP (and probably as easy to 
implement
in C), but IMHO could be nice addition to set of array related functions 
in PHP.

If the response to this e-mail will be positive, I will prepare RFC.
We should also discuss order of arguments as the functions are similar 
to both
array_search/in_array with condition-array and array_filter with
array-condition, but as you can see above I am leaning towards 
condition-array.

Looking forward to hearing your thoughts.

Best regards,
Janusz