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фильтр не описан

wp_query_search_exclusion_prefix хук-фильтр . WP 4.7.0

Filters the prefix that indicates that a search term should be excluded from results.

Использование

add_filter( 'wp_query_search_exclusion_prefix', 'filter_function_name_9482' );
function filter_function_name_9482( $exclusion_prefix ){
	// filter...

	return $exclusion_prefix;
}
$exclusion_prefix(строка)
The prefix. Returning an empty value disables exclusions.
По умолчанию: '-'

Где используется хук

Код хука

Фрагмент из: wp-includes/class-wp-query.php VER 4.9.8
...
			}
		}

		$n = ! empty( $q['exact'] ) ? '' : '%';
		$searchand = '';
		$q['search_orderby_title'] = array();

		/**
		 * Filters the prefix that indicates that a search term should be excluded from results.
		 *
		 * @since 4.7.0
		 *
		 * @param string $exclusion_prefix The prefix. Default '-'. Returning
		 *                                 an empty value disables exclusions.
		 */
		$exclusion_prefix = apply_filters( 'wp_query_search_exclusion_prefix', '-' );

		foreach ( $q['search_terms'] as $term ) {
			// If there is an $exclusion_prefix, terms prefixed with it should be excluded.
			$exclude = $exclusion_prefix && ( $exclusion_prefix === substr( $term, 0, 1 ) );
			if ( $exclude ) {
				$like_op  = 'NOT LIKE';
				$andor_op = 'AND';
				$term     = substr( $term, 1 );
			} else {
				$like_op  = 'LIKE';
				$andor_op = 'OR';
			}

			if ( $n && ! $exclude ) {
				$like = '%' . $wpdb->esc_like( $term ) . '%';
...