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<?php $content = <<<CONTENT a @tag CONTENT; $matches = array(); var_dump(preg_match('/^a/', $content, $matches, 0, 0) === 1); var_dump(preg_match('/^(\A|\n)\w*@/', $content, $matches, 0, 1) === 1);
Output for 4.3.3 - 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, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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
bool(true) bool(false)
Output for 4.3.0 - 4.3.2
Warning: Wrong parameter count for preg_match() in /in/BXpJU on line 8 bool(false) Warning: Wrong parameter count for preg_match() in /in/BXpJU on line 9 bool(false)

preferences:
190.64 ms | 401 KiB | 322 Q