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function is not described

_get_non_cached_ids() WP 3.4.0

Retrieve IDs that are not already present in the cache.

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

Int[]. Array of IDs not present in the cache.

Usage

_get_non_cached_ids( $object_ids, $cache_key );
$object_ids(int[]) (required)
Array of IDs.
$cache_key(string) (required)
The cache bucket to check against.

Changelog

Since 3.4.0 Introduced.

Code of _get_non_cached_ids() WP 5.7

<?php
function _get_non_cached_ids( $object_ids, $cache_key ) {
	$non_cached_ids = array();
	$cache_values   = wp_cache_get_multiple( $object_ids, $cache_key );

	foreach ( $cache_values as $id => $value ) {
		if ( ! $value ) {
			$non_cached_ids[] = (int) $id;
		}
	}

	return $non_cached_ids;
}