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<?php $arr = [ 'foo', 'foo', 'bar', 'baz', 'baz' ]; array_walk($arr, function (&$item, $k) use ($arr) { $lower = mb_strtolower($item, 'utf-8'); foreach ($arr as $i => $v) { if ($i !== $k && $lower === mb_strtolower($v, 'utf-8')) { $item = null; } } }); var_dump($arr);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
array(5) { [0]=> NULL [1]=> NULL [2]=> string(3) "bar" [3]=> NULL [4]=> NULL }
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(5) { [0]=> NULL [1]=> NULL [2]=> string(3) "bar" [3]=> NULL [4]=> NULL }
preferences:
135.84 ms | 402 KiB | 173 Q