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<?php function flatten_array($simple){ static $outputs=array(); foreach ( $simple as $value) { if(is_array($value)){ flatten_array($value); } else { $outputs[]=$value; } } return $outputs; } $eg=['s'=>['p','n'=>['t']]]; $out=flatten_array($eg); print_r($out); echo "\n---\n"; $out=flatten_array($eg); print_r($out);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
Array ( [0] => p [1] => t ) --- Array ( [0] => p [1] => t [2] => p [3] => t )

preferences:
116.58 ms | 408 KiB | 5 Q