woocommerce_cart_id │ filter-hook │ WC 1.0

Usage

add_filter( 'woocommerce_cart_id', 'wp_kama_woocommerce_cart_id_filter', 10, 5 );

/**
 * Function for `woocommerce_cart_id` filter-hook.
 * 
 * @param  $md5( implode() ) 
 * @param  $product_id       
 * @param  $variation_id     
 * @param  $variation        
 * @param  $cart_item_data   
 *
 * @return 
 */
function wp_kama_woocommerce_cart_id_filter( $md5( implode() ), $product_id, $variation_id, $variation, $cart_item_data ){

	// filter...
	return $md5( implode() );
}

$md5( implode() )

-

$product_id

-

$variation_id

-

$variation

-

$cart_item_data

-

Where the hook is called

return apply_filters( 'woocommerce_cart_id', md5( implode( '_', $id_parts ) ), $product_id, $variation_id, $variation, $cart_item_data );

Where the hook is used in WooCommerce