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<?php //with ^ $str = " {user:fname} and the last name = {user:lname}"; preg_match_all("/^\{(\w):(\w)\}/", $str, $matches); print_r($matches); //without ^ preg_match_all("/\{(\w+):(\w+)\}/", $str, $matches2); print_r($matches2);
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 - 5.6.40, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => Array ( ) [1] => Array ( ) [2] => Array ( ) ) Array ( [0] => Array ( [0] => {user:fname} [1] => {user:lname} ) [1] => Array ( [0] => user [1] => user ) [2] => Array ( [0] => fname [1] => lname ) )

preferences:
331.41 ms | 406 KiB | 460 Q