_rest_array_intersect_key_recursive() │ WP 5.3.0

Recursively computes the intersection of arrays using keys for comparison.

Internal function — this function is designed to be used by the kernel itself. It is not recommended to use this function in your code.

No Hooks.

Returns

Array. An associative array containing all the entries of array1 which have keys that are present in all arguments.

Usage

_rest_array_intersect_key_recursive( $array1, $array2 );
$array1(array) (required)
The array with master keys to check.
$array2(array) (required)
An array to compare keys against.

Changelog

Since 5.3.0 Introduced.

_rest_array_intersect_key_recursive() code WP 7.0

wp-includes/rest-api.php 
function _rest_array_intersect_key_recursive( $array1, $array2 ) {
	$array1 = array_intersect_key( $array1, $array2 );
	foreach ( $array1 as $key => $value ) {
		if ( is_array( $value ) && is_array( $array2[ $key ] ) ) {
			$array1[ $key ] = _rest_array_intersect_key_recursive( $value, $array2[ $key ] );
		}
	}
	return $array1;
}