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<?php $array = [null => 42, false => 43]; var_dump(array_key_exists(null, $array)); // true var_dump(array_key_exists('', $array)); // true var_dump(array_key_exists(false, $array)); // true var_dump(array_key_exists(0, $array)); // true var_dump(array_key_exists(0.0, $array)); // true print count($array). " elements in the array\n";
Output for 8.5.0 - 8.5.6
Deprecated: Using null as an array offset is deprecated, use an empty string instead in /in/ITVEd on line 3 Deprecated: Using null as the key parameter for array_key_exists() is deprecated, use an empty string instead in /in/ITVEd on line 5 bool(true) bool(true) bool(true) bool(true) bool(true) 2 elements in the array
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.21
bool(true) bool(true) bool(true) bool(true) bool(true) 2 elements in the array
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