@safe containers with std.experimental.allocator

[Chris Wright via Digitalmars-d]

On Sat, 21 Jan 2017 04:01:06 +0000, bitwise wrote:

> On Saturday, 21 January 2017 at 02:47:49 UTC, bitwise wrote:
>> [...]
> 
> I can see that 'TypedAllocator' exists, but with a different interface
> than the rest of the allocators. Why wouldn't all allocators just have a
> common interface?

TypedAllocator combines several allocators, using a series of Policies to 
determine which one to use for a given type.

The interface for allocators is mostly given by IAllocator and mostly 
implemented with UFCS functions defined in 
std.experimental.allocator.package. The one aspect that isn't given with 
IAllocator (because OOP doesn't support it well) is that not all 
allocators have to support aligned allocations.

TypedAllocator overrides some of those default implementations in order 
to use its Policies. It doesn't expose the untyped variants so that you 
can't get around its Policies.

Unfortunately, there's no way to require that a TypedAllocator return an 
aligned allocation aside from using an aligned allocator for the relevant 
policy.