Re: [Haskell-cafe] All-fail case in asum

On Fri, Jun 10, 2016 at 05:37:41PM +0300, Юрий Сыровецкий (Yuriy Syrovetskiy) wrote:

It is so because in base library

asum = foldr (<|>) empty

What if it was defined

asum [] = empty asum [x:xs] = x <|> asum xs

Those are the same (assuming you mean (x:xs) instead of [x:xs]). Tom