struct Unique(T)

[ChrisG]

On Thursday, 7 November 2013 at 01:09:45 UTC, Chris Cain wrote:
> On Thursday, 7 November 2013 at 00:07:25 UTC, ChrisG wrote:
>> My question is: what's the status of D's struct Unique? It 
>> looks like struct RefCounted is current, but I can't tell with 
>> Unique. There's several comments in the source that say: 
>> doesn't work yet. It seems like some of it could be made to 
>> work as intended. For example, the commented out code to 
>> disallow construction via an lvalue:
>
> I'm pretty sure things like Unique have been neglected for 
> awhile. Probably for a decent reason, but a lot of language 
> features have been landing that could help polish it up a bit 
> more.
>
>> Next, I'd like to be able to use a custom deleter. For 
>> example, a naive implementation I could write would be 
>> something like:
>>
>> ... snip ...
>>
>> So, I could do things like:
>>
>> Unique2!(int, "free") i1 = cast(int*)malloc(int.sizeof); // 
>> lame example
>>
>> A real implementation would allow more interesting deleters in 
>> the form of delegates, but I'm already stretching my D skillz.
>
> I think Unique will probably be getting something along those 
> lines reasonably shortly, but std.allocator will have to be 
> fully completed first.
>
> http://forum.dlang.org/thread/l4btsk$5u8$1@digitalmars.com
>
> Once that's done we'll see some memory management schemes like 
> what you're suggesting be implemented. But it's probably not a 
> good idea to add that stuff before we figure out a good way to 
> use it with the new std.allocator effectively.

Ok, thanks. That does make some sense to me. I read some of the 
std.allocator thread. I'll take a look at that code and see what 
I can make of it.