Using the De Bruijn notation, it is possible to define lambda terms as: data BTerm = BVar Int | BLam BTerm | BApp BTerm BTerm Or using the usual notation, data Term = Var String | Lam String Term |...

I've been programming for a long time (too long, actually), but I'm really struggling to get a handle on the terms "Free Variables" and "Bound Variables". Most of the "explanations" I've found onl...