Re: [Haskell-cafe] IO (Either a Error) question

David Menendez writes:

That does not invoke fail.

Let's take a simpler example: do { x <- Nothing; stmt }. This translates to

let ok x = do { stmt } ok _ = fail "..." in Nothing >>= ok

By the definition of (>>=) for Maybe, 'ok' is never called.

As I said in another email: does not the "x <- Nothing" itself call fail as it expects x to be an actual value wrapped in Just? -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com