Re: [Haskell-cafe] Different semantics in "identical" do statement?

Daniel Peebles wrote:

I vaguely remember on IRC someone pointing out that the Parsec monad broke one of the laws. I think return _|_ >> x === _|_ which could be causing your problem. I may be wrong though.

Confirmed, working in the parsec monad Prelude Text.Parsec> runP (do {x <- return undefined; return 10}) () "" "" *** Exception: Prelude.undefined In the IO Monad Prelude Text.Parsec> do {x <- return undefined; return 10} 10 Should be fixed. -- View this message in context: http://www.nabble.com/Different-semantics-in-%22identical%22-do-statement--t... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.