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filter is not described

wp_unique_post_slug_is_bad_attachment_slug filter-hook . WP 3.1.0

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

Usage

add_filter( 'wp_unique_post_slug_is_bad_attachment_slug', 'filter_function_name_6702', 10, 2 );
function filter_function_name_6702( $bad_slug, $slug ){
	// filter...

	return $bad_slug;
}
$bad_slug(true/false)
Whether the slug would be bad as an attachment slug.
$slug(string)
The post slug.

Where the hook is called

wp_unique_post_slug()
wp_unique_post_slug_is_bad_attachment_slug
wp-includes/post.php 3934
if ( $post_name_check || in_array( $slug, $feeds ) || 'embed' === $slug || apply_filters( 'wp_unique_post_slug_is_bad_attachment_slug', false, $slug ) ) {

Where the hook is used (in WP core)

Does not used.