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run code in 300+ PHP versions simultaneously
<?php $p = array( 'test' => 7, 'checkbox_2' => 'on', 'checkbox_4' => 'on', 'checkbox_10' => 'on', 'Submit' => '', 'name' => 20, ); foreach ($p as $key => $val) { echo substr($key, 0, strlen('checkbox_')) . PHP_EOL; }
Output for 4.3.10 - 4.3.11, 4.4.0 - 4.4.9, 5.0.2 - 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 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
test checkbox_ checkbox_ checkbox_ Submit name
Output for 4.3.0 - 4.3.9, 5.0.0 - 5.0.1
Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 testPHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 checkbox_PHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 checkbox_PHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 checkbox_PHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 SubmitPHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/TLuIl on line 13 namePHP_EOL

preferences:
270.57 ms | 402 KiB | 456 Q