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run code in 300+ PHP versions simultaneously
<?php $row = array( 'useless' => 42, 'useful' => 'orange', 'useless_too' => 'banana', 'useful_too' => 'apples'); foreach ($row as $key1=>$value){ $pos = strpos($key1,'useful'); if($pos==-1) unset($row[$key]); } print_r($row);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 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 ( [useless] => 42 [useful] => orange [useless_too] => banana [useful_too] => apples )
preferences:
225.76 ms | 406 KiB | 354 Q