3v4l.org

run code in 300+ PHP versions simultaneously
<?php $data = <<<DATA this will = ({match1}) this should = not ({match2}) ({match3}) DATA; $pattern = "~[^\w\s]\h*\K\({\w+}\)~"; preg_match_all($pattern, $data, $matches); print_r($matches[0]);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Array ( [0] => ({match1}) )

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