[jgwil2]

I think I agree with you (though I would favor T, U, V as the sequence).

What would the alternative look like in what you wrote? In and Out? Range and Domain? Generic type variables are often too abstract to give a sensible name to.

This is the one "bad habit" that I think is a bit silly - naming conventions can vary by project.

[SmellyPotato22]

In the context I am thinking about, writing a generic iterator, you have 0 context of the what the concrete types will ever be.