Why is D slower than LuaJIT?

[bearophile]

Andrei:

> I'm thinking what to do about iota, which has good features but exacts 
> too much cost on tight loop performance. One solution would be to define 
> iota to be the simple, forward range that I defined as Iota2 in my 
> previous post. Then, we need a different name for the full-fledged iota 
> (random-access, has known length, iterates through the same numbers 
> forward and backward etc). Ideas?

Is improving the compiler instead an option?

Bye,
bearophile