All items must implement Dyankov\ShoppingCart\Contracts\ShoppingCartItem so they can be put in the cart. Coupons must implement Dyankov\ShoppingCart\Contracts\ShoppingCartCoupon.

Put item in the cart:

$cart = Dyankov\ShoppingCart\ShoppingCart();
$cart->put($shoppingCartItem);

Take item out of the cart:

$cart = Dyankov\ShoppingCart\ShoppingCart();
$cart->put($shoppingCartItem);
$cart->takeOut($shoppingCartItem);

Cart total:

$cart = Dyankov\ShoppingCart\ShoppingCart();
$cart->put($shoppingCartItem);
$cart->total();

Apply coupon:

$cart = Dyankov\ShoppingCart\ShoppingCart();
$cart->put($shoppingCartItem);
$cart->applyCoupon($shoppingCartCoupon);