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filter is not described

wp_unique_term_slug_is_bad_slug filter-hook . WP 4.3.0

Filters whether the proposed unique term slug is bad.

Usage

add_filter( 'wp_unique_term_slug_is_bad_slug', 'filter_function_name_7877', 10, 3 );
function filter_function_name_7877( $needs_suffix, $slug, $term ){
	// filter...

	return $needs_suffix;
}
$needs_suffix(true/false)
Whether the slug needs to be made unique with a suffix.
$slug(string)
The slug.
$term(object)
Term object.

Where the hook is called

wp_unique_term_slug()
wp-includes/taxonomy.php 2543
if ( apply_filters( 'wp_unique_term_slug_is_bad_slug', $needs_suffix, $slug, $term ) ) {

Where the hook is used (in WP core)

Does not used.