[acomar]

Yep, you've got it exactly right.

The problem for dynamic type systems is how do you enforce 3? Do you care to?

[geon]

I suppose you could write a sort of safe Maybe template class in c++. You could pass in two callbacks to handle Just and Nothing respectively. It would be really ugly, but should work, right?

[pubby]

Yeah, a function taking two callbacks is what I had in mind. This works in dynamic typed languages too, although obviously not as well.