3 ms·
Is there some reason the given answer for forming I out of BCKW isn't the shortest possibility? I jumped to I = WK, while the given answer is I = CKC.
by thedufer 6y ago
Is there some reason the given answer for forming I out of BCKW isn't the shortest possibility? I jumped to I = WK, while the given answer is I = CKC.
- Jtsummers 6y agoI did as well, and actually came here to see if anyone else had commented on that. WKx => Kxx => x CKCx => KxC => x After the first application they both end up in essentially the same state (the `C` in the second case is going to be discarded so it really doesn't matter what's there).
- oisdk 6y agoYes! Basically I preferred solutions that avoided W, since you're then working in a subset of the language that is definitely terminating and affine. (although in this case I just didn't find I = WK) I should actually add a note about that, since a few people have pointed it out.
- thedufer 6y ago> Basically I preferred solutions that avoided W, since you're then working in a subset of the language that is definitely terminating and affine. Ah, that makes a lot of sense. I mostly just thought my version was the obvious one - my first thought of how to do nothing was to duplicate something and then drop one of the dupes. I have very little grounding in lambda calculus, though, and generally find the other combinators harder to reason about.