On 10/1/14, 8:48 AM, Oren Tirosh wrote:
On Tuesday, 30 September 2014 at 19:10:19 UTC, Marc Schütz wrote:
[...]
I'm convinced this isn't necessary. Let's take `setExtension()` as an
example, standing in for any of a class of similar functions. This
function allocates memory, returns it, and abandons it; it gives up
ownership of the memory. The fact that the memory has been freshly
allocated means that it is (head) unique, and therefore the caller (=
library user) can take over the ownership. This, in turn, means that
the caller can decide how she wants to manage it.
Bingo. Have some way to mark the function return type as a unique
pointer.
I'm skeptical about this approach (though clearly we need to explore it
for e.g. passing ownership of data across threads). For strings and
other "casual" objects I think we should focus on GC/RC strategies. This
is because people do things like:
auto s = setExtension(s1, s2);
and then attempt to use s as a regular variable (copy it etc). Making s
unique would make usage quite surprising and cumbersome.
Andrei
