[xmonad] Article about xmonad not making X errors?

[Don Stewart]

asgaroth_:
> Joseph Garvin wrote:
> > I recall reading at some point an article or blog post that discussed
> > how XMonad leveraged the type system to guarantee that X errors
> > couldn't occur. But no matter how much googling I do now I can't find
> > it; I musn't be using the right search terms. Anyone know where it is?
> 
> The type system can't guarantee that xmonad produces no X errors, since
> it relies on the ffi and secondly, matching types don't imply
> correctness, especially when dealing with IO-ish stuff. I think you

We do use the type system for a number of invariants, though. But by
no means can we guarantee *no* errors -- we'd need a specification of
the X server in a theorem prover to even start... :)
--   Don