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<?php $regex = '/X(*MARK:A)Y|X(*MARK:B)Z/'; preg_match($regex, "XY", $matches); echo $matches['MARK'], "\n"; // A preg_match($regex, "XZ", $matches); echo $matches['MARK'], "\n"; // B preg_match($regex, "XP", $matches); echo $matches['MARK'], "\n"; // Should also be B, instead: Notice: Undefined index: MARK
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
A B Warning: Undefined array key "MARK" in /in/tMkan on line 12
Output for 5.6.0 - 5.6.25, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.31, 7.4.0 - 7.4.33
A B Notice: Undefined index: MARK in /in/tMkan on line 12
Output for 7.3.32 - 7.3.33
A B
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