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_rest_array_intersect_key_recursive() WP 5.3.0

Recursively computes the intersection of arrays using keys for comparison.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

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.

Code of _rest_array_intersect_key_recursive() WP 5.7.2

<?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;
}