These aren’t quite the same. With “x && x->y”, you’re using a boolean to encode the assumption that “x” is valid, but with “x >>= getY”, the type system has a p

These aren’t quite the same. With “x && x->y”, you’re using a boolean to encode the assumption that “x” is valid, but with “x >>= getY”, the type system has a proof, which makes refactoring safer.