Re: CQRS cross aggregate interaction + private state

Ah, ofcourse, it's how the old MUD games works 

player.Eat(apple);
apple.CanBeEaten(player);

I knew this, just wanted to see if your all awake *jk*

--- In domaindrivendesign <at> yahoogroups.com, Nuno Lopes <nbplopes@...> wrote:
>
> Maybe I can help:
> 
> class Product : IOrderableItem
> 	....
> 	void TestAddOrder(Order order, double qty)
> 	{
> 		if (this.IsObsolete())
> 			throw new BusinessException("An obsolete product cannot be ordered")
> 	}
> 
> 	void Order (Order o, double qty) {
> 		o.AddItem(this, this.REF, this.Description, this.Price, qty) 
> 	}
> 	.....
> 
> class Order 
> {
> 	void AddItem(IOrderableItem i, string REF, string description, double price, double qty)
> 	{
> 		...
> 		i.TestAddOrder(this, qty)
> 		......
> 		this.DoAddItem(new OrderLine(REF, description, price, qty));
> 	}
> }
> 
> Hope it helps.
> 
> Nuno
> 
> 
> On Feb 9, 2010, at 12:38 PM, rogeralsing wrote:
> 
> > If entities only have private state, how do you deal with interaction between aggregates?
> > 
> > e.g.
> > 
> > product = GetProduct(123);
> > order.AddProduct(product,3);
> > 
> > Lets for the sake of the argument that addproduct can not occur if product is marked as obsolete.
> > 
> > How would you deal with that?
> > What's the idea behind completely private state?
> > Why shouldn't order be able to read properties on product?
> > 
> >
>

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