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filter is not described

wp_insert_post_parent filter-hook . WP 3.1.0

Filters the post parent -- used to check for and prevent hierarchy loops.

Usage

add_filter( 'wp_insert_post_parent', 'filter_function_name_9054', 10, 4 );
function filter_function_name_9054( $post_parent, $post_ID, $new_postarr, $postarr ){
	// filter...

	return $post_parent;
}
$post_parent(int)
Post parent ID.
$post_ID(int)
Post ID.
$new_postarr(array)
Array of parsed post data.
$postarr(array)
Array of sanitized, but otherwise unmodified post data.

Where the hook is called

wp_insert_post()
wp-includes/post.php 3461
$post_parent = apply_filters( 'wp_insert_post_parent', $post_parent, $post_ID, $new_postarr, $postarr );

Where the hook is used (in WP core)

wp-includes/default-filters.php 151
add_filter( 'wp_insert_post_parent', 'wp_check_post_hierarchy_for_loops', 10, 2 );