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<?php $pattern = '~ (?<animal>) (?<color>) ^ (?<animal>DOG|CAT)? (?<color>RED|BLUE)? $ ~xiJ'; if ( preg_match($pattern, 'dog', $m) ) print_r(array_filter($m, 'is_string', ARRAY_FILTER_USE_KEY));

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32.08 ms | 406 KiB | 5 Q