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<?php $noAcronyms = 'oneTwoThreeFour'; var_export(preg_split('~^[^A-Z]+\K|[A-Z][^A-Z]+\K~', $noAcronyms, 0, PREG_SPLIT_NO_EMPTY)); echo "\n---\n"; var_export(preg_match_all('~[A-Z]?[^A-Z]+~', $noAcronyms, $out) ? $out[0] : []);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 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 - 8.3.6
array ( 0 => 'one', 1 => 'Two', 2 => 'Three', 3 => 'Four', ) --- array ( 0 => 'one', 1 => 'Two', 2 => 'Three', 3 => 'Four', )
preferences:
195.9 ms | 403 KiB | 211 Q