$assoc_arr = array_reduce($arr, function ($result, $item) { $result[$item['text']] = $item['id']; return $result; }, array());
Recommendation: If you are interested in fast PHP for your WordPress site, check out this great PHP/WP benchmark-post from Kinsta, where you can get great managed WordPress hosting with the best support and performance optimizing technical addons like Redis and ElasticSearch.
The snippets story
I just ran into a problem using array_map on associative arrays, like the following one:
$arr = array( array( 'id' => 22, 'text' => 'Lorem' ), array( 'id' => 25, 'text' => 'ipsum' ), );
From this array, I wanted to create another, associative array, with the following structure:
$assoc_arr = array( 'Lorem' => 22, 'ipsum' => 25 );
My first guess was the array_map function, but I had to realize that there is no way to manipulate the keys of the resulting array. After some googling, I discovered, that it is array_reduce you have to use to simulate array_map on associative arrays.
ps: I know, a simple foreach would have done the trick, but once on the path of functional programming, I didn’t want to leave it that fast 🙂