Circular Buffer

[Frustrated]

I'm in need of a circular buffer/array. I am using 
std.container.array to avoid the GC. I suppose I could copy and 
modify the code but is there any easier way? It looks like it is 
defined as templates so could I somehow hijack the code and 
modify only what is needed rather than duplicate a lot of stuff? 
(or maybe someone could just add it to the library... circular 
arrays are useful ya know ;)