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<?php $array = [ "0" => 'Zero', 'foo' => 'Foo', 1 => 'One', ]; var_dump( array_key_exists(0, $array), array_key_exists("0", $array), array_key_exists(1, $array), array_key_exists("1", $array), );
Output for 8.1.34, 8.2.27 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
bool(true) bool(true) bool(true) bool(true)
preferences:
49.87 ms | 406 KiB | 5 Q