[swift-users] Are value semantics really appropriate in a diagramming app?

[Rick Mann]

> On Aug 1, 2016, at 02:25 , Rimantas Liubertas <rimantas at gmail.com> wrote:
> 
> 
> I did. That's one of the two talks I mentioned.
> 
> Well, so they did cover this, didn't they? You move item, you get the new struct with the new position. And if you save the old one, you have a cheap way to implement undo.

That's the other problem, undo. Presumably, the copy-on-write semantics make this form of undo efficient, both in terms of making the copy for each operation, and in terms of the amount of memory required (because only fine-grained copies are made). But if the model is large and complicated, I'd be worried about the performance implications of this.

Maybe I'll try it, see how it works.


-- 
Rick Mann
rmann at latencyzero.com