woocommerce_before_output_product_categories filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_before_output_product_categories', 'filter_function_name_1506' );
function filter_function_name_1506( $string ){
	// filter...

	return $string;
}

$string

-

Where the hook is called

'before'    => apply_filters( 'woocommerce_before_output_product_categories', '' ),

Where in WP core the hook is used WooCommerce