Packing enums

[qznc via Digitalmars-d-learn]

I stumbled upon this interesting programming challenge [0], which 
imho should be possible to implement in D. Maybe someone here 
wants to try.

Task: Given two enums with less than 256 states, pack them into 
one byte and provide convenient accessor functions.

Something like this:

enum X { A, B, C };
enum Y { foo, bar, baz };
alias both = TwoEnums!(X,Y);
static assert(both.sizeof == 1);
both z;
z.X = B;
z.Y = bar;

Of course, you can generalize to "n enums packed into a minimal 
number of bytes".


[0] https://news.ycombinator.com/item?id=9800231