On: Maybe Not [video]

[JadeNB]

But you mentioned simplifying `Maybe (Maybe a)` to `Maybe a`, which your `collect` doesn't do (at least not directly).

(Also, shouldn't `Either[Bool, a]` (which I don't know how to make sense of) be `Either Bool a`? Even with this signature, I'm not sure what the implementation would be, and Hoogle doesn't turn up any obviously correct results ( https://www.haskell.org/hoogle/?hoogle=collect https://www.haskell.org/hoogle/?hoogle=Maybe+%28Maybe+a%29+-... ), but that's probably my fault.)

[dllthomas → JadeNB]

I think the obvious implementation is `maybe (Left False) (maybe (Left True) Right)`

If we have a value then we clearly have both layers. If we don't have a value then we need to distinguish Nothing from Just Nothing by way of the book.

[JadeNB → dllthomas]

Oh, I see; we're thinking of `Maybe a` as `a + ()`, and then identifying `(a + ()) + ()` with `a + (() + ())` and then `() + ()` with `Bool`. Thanks!

[dllthomas → JadeNB]

Right, exactly!