std.allocator ready for some abuse

[Andrei Alexandrescu]

Hello,


I know it's been a long wait. Hopefully it was worth it. The alpha 
release of untyped allocators is ready for tire-kicking and a test drive.

Code: https://github.com/andralex/phobos/blob/allocator/std/allocator.d

Dox: http://erdani.com/d/phobos-prerelease/std_allocator.html

Warning: this is alpha quality. Unit tests are thin, and there are no 
benchmarks. Both would be appreciated, particularly benchmarks to 
validate the gains (which I speculate can be very sizable) of 
custom-built, special-purpose allocators compared to traditional allocators.

I acknowledge I'm clearly in no position to evaluate this design. I have 
been knocking around it for long enough to have no idea how easy it is 
to get into it from the outside, or how good it is. By all signs I could 
gather this feels like good design, and one of the best I've ever put 
together. The allocators defined have an archetypal feeling, are 
flexible both statically and dynamically, and morph and combine in 
infinite ways.

CAllocator and CAllocatorImpl make the link between the static and 
dynamic worlds. Once an allocator is assembled out of pieces and finely 
tuned, wrapping it in a dynamic API is a snap.

Please destroy! I've literally sweat as I'm sending this :o).


Andrei