On 12/27/11 2:24 AM, Jonathan M Davis wrote:
On Monday, December 26, 2011 20:47:50 Andrei Alexandrescu wrote:
1. "Basic" containers - reference semantics, using classic garbage
collection
2. Reference counted containers - still reference semantics, using
reference counting
3. COW containers - value semantics, using reference counting to make
copying O(1).
How to we provide an Apple-style nice wrapping to all of the above?
I'd be inclined to argue that reference counting and COW should be kept
separate as opposed to being different versions of the same type simply to make
it easier to understand. Not to mention, how often is COW needed for
containers? It's useful for many things, but it's only useful for value-type
containers, and the use cases for value-type containers are fairly limited I
should think. I'm sure that they're very useful under certain circumstances,
but as has been pointed out in the past, the fact that C++ defaults to having
value-type containers is a big problem. So, I don't think that it's a bad
thing to make it possible to have value-type containers and/or COW containers,
but if they're going to seriously complicate things, then they should be
separate IMHO. They're more specialized as opposed to being the normal use
case.
Someone coming from C++ would instantly recognize value containers, and
might prefer using them in spite our judgment that reference containers
are preferable. COW is a great bridge because it keeps the copy
constructor cheap.
By the way, I'm surprised to see the use of delete in that code, since delete
is supposed to be going away.
It's just a prototype.
Andrei
