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run code in 300+ PHP versions simultaneously
<?php $string = <<<DATA {start} SubPattern1 {end} {start} SubPattern2 {end} {start} {start}SubPattern3{end} {end} DATA; preg_match_all('/{start}((?:(?:(?!{(?:start|end)}).)+|(?R))*){end}/', $string, $result); print_r($result);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
Array ( [0] => Array ( [0] => {start} SubPattern1 {end} [1] => {start} SubPattern2 {end} [2] => {start} {start}SubPattern3{end} {end} ) [1] => Array ( [0] => SubPattern1 [1] => SubPattern2 [2] => {start}SubPattern3{end} ) )

preferences:
129.79 ms | 409 KiB | 5 Q