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<?php echo "\w without the \u flag should result in int(0) in all PHP versions\n"; var_dump(preg_match('/\w/', 'ä')); echo "\n\w with the \u flag used to result in int(1) in PHP <7.3!\n"; var_dump(preg_match('/\w/u', 'ä')); echo "\n\pL instead of \w used to result in int(1) in all PHP versions\n"; var_dump(preg_match('/\pL/u', 'ä'));
Output for 5.3.4 - 7.4.6
\w without the \u flag should result in int(0) in all PHP versions int(0) \w with the \u flag used to result in int(1) in PHP <7.3! int(1) \pL instead of \w used to result in int(1) in all PHP versions int(1)
Output for 4.4.0 - 4.4.9, 5.0.5 - 5.3.3
\w without the \u flag should result in int(0) in all PHP versions int(0) \w with the \u flag used to result in int(1) in PHP <7.3! int(0) \pL instead of \w used to result in int(1) in all PHP versions int(1)
Output for 4.3.11, 5.0.0 - 5.0.4
\w without the \u flag should result in int(0) in all PHP versions int(0) \w with the \u flag used to result in int(1) in PHP <7.3! int(0) \pL instead of \w used to result in int(1) in all PHP versions Warning: preg_match(): Compilation failed: PCRE does not support \L, \l, \N, \P, \p, \U, \u, or \X at offset 1 in /in/uJKEC on line 10 bool(false)
Output for 4.3.0 - 4.3.10
\w without the \u flag should result in int(0) in all PHP versions int(0) \w with the \u flag used to result in int(1) in PHP <7.3! int(0) \pL instead of \w used to result in int(1) in all PHP versions Warning: Compilation failed: PCRE does not support \L, \l, \N, \P, \p, \U, \u, or \X at offset 1 in /in/uJKEC on line 10 bool(false)