Is there something like isInputRange for allocators, I tried looking for something but couldn't find anything? If not, why not?

On Monday, 30 November 2015 at 14:21:49 UTC, Tofu Ninja wrote:
> Is there something like isInputRange for allocators, I tried looking for something but couldn't find anything? If not, why not?

Aka, some way to check that type T is an allocator.

On 01/12/15 3:23 AM, Tofu Ninja wrote:
> On Monday, 30 November 2015 at 14:21:49 UTC, Tofu Ninja wrote:
>> Is there something like isInputRange for allocators, I tried looking
>> for something but couldn't find anything? If not, why not?
>
> Aka, some way to check that type T is an allocator.

Doesn't look like it.

bool isAllocator(Alloc)() pure {
	return __traits(compiles, {IAllocator alloc = new CAllocatorImpl!Alloc;});
}

That should work however.

On Tuesday, 1 December 2015 at 03:05:34 UTC, Rikki Cattermole wrote:
> On 01/12/15 3:23 AM, Tofu Ninja wrote:
>> On Monday, 30 November 2015 at 14:21:49 UTC, Tofu Ninja wrote:
>>> Is there something like isInputRange for allocators, I tried looking
>>> for something but couldn't find anything? If not, why not?
>>
>> Aka, some way to check that type T is an allocator.
>
> Doesn't look like it.
>
> bool isAllocator(Alloc)() pure {
> 	return __traits(compiles, {IAllocator alloc = new CAllocatorImpl!Alloc;});
> }
>
> That should work however.

I think that `is(CAllocatorImpl!Alloc)` should work too then.

On Tuesday, 1 December 2015 at 08:58:56 UTC, BBaz wrote:
> I think that `is(CAllocatorImpl!Alloc)` should work too then.

According to the 'is' version, int is an allocator. No idea why it thinks this works...

enum isAllocator(Alloc) = is(CAllocatorImpl!Alloc);
static assert(isAllocator!int);

This seems to work well though...
enum isAllocator(Alloc) = __traits(compiles, {IAllocator alloc = new CAllocatorImpl!Alloc;});

static assert(isAllocator!Mallocator);
static assert(isAllocator!GCAllocator);
static assert(!isAllocator!int);

On Tuesday, 1 December 2015 at 12:37:12 UTC, Tofu Ninja wrote:
> On Tuesday, 1 December 2015 at 08:58:56 UTC, BBaz wrote:
>> I think that `is(CAllocatorImpl!Alloc)` should work too then.
>
> According to the 'is' version, int is an allocator. No idea why it thinks this works...

Me neither, actually, and to be honnest, I didn't test, but from the version that uses the "compiles" traits, I thought that testing if the type generated from a template instantiation is valid then it would be equivalent...Apologies, I didn't meant to lead anybody in the wrong direction.