[challenge] Limitation in D's metaprogramming

[Nick Sabalausky]

"Jonathan M Davis" <jmdavisProg at gmx.com> wrote in message 
news:mailman.715.1287449256.858.digitalmars-d at puremagic.com...
>
> One word: monads.
>
> Now, to get monads to work, you're going to have to be fairly organized 
> about
> it, but that would be the classic solution to not being able to have or 
> alter
> global state and yet still be able to effectively have global state.
>

Oh yea, I've heard about them but don't have any real experience with them. 
Any FP experts know whether or not monads are known to be constructible from 
purely-FP building blocks? I always assumed "no", and that monads really 
just came from a deliberate compiler-provided hole in the whole purity 
thing, but maybe I'm wrong? (That would be quite interesting: constructing 
impurity from purity.)