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filter is not described

wp_unique_post_slug_is_bad_hierarchical_slug filter-hook . WP 3.1.0

Filters whether the post slug would make a bad hierarchical post slug.

Usage

add_filter( 'wp_unique_post_slug_is_bad_hierarchical_slug', 'filter_function_name_4430', 10, 4 );
function filter_function_name_4430( $bad_slug, $slug, $post_type, $post_parent ){
	// filter...

	return $bad_slug;
}
$bad_slug(true/false)
Whether the post slug would be bad in a hierarchical post context.
$slug(string)
The post slug.
$post_type(string)
Post type.
$post_parent(int)
Post parent ID.

Where the hook is called

wp_unique_post_slug()
wp-includes/post.php 3964
if ( $post_name_check || in_array( $slug, $feeds ) || 'embed' === $slug || preg_match( "@^($wp_rewrite->pagination_base)?\d+$@", $slug )  || apply_filters( 'wp_unique_post_slug_is_bad_hierarchical_slug', false, $slug, $post_type, $post_parent ) ) {

Where the hook is used (in WP core)

Does not used.