Re: [Haskell-cafe] Stupid question #374: why is MaybeT not in the standard library?

On Mon, Dec 22, 2008 at 6:52 PM, Antoine Latter wrote:

2008/12/22 Luke Palmer :

...

Yeah, it'd be useful. Doesn't really matter, though, because it's on Hackage (http://hackage.haskell.org), so it's just a cabal install MaybeT away. Now that cabal and cabal-install are reasonably mature, we really don't have to worry about what's blessed as "standard" anymore. :-)

Although I still had to use my own because I wanted a MonadPlus instance. I would offer a patch, but since there's more than one useful MonadPlus instance for MaybeT it probably still wouldn't be right for everyone.

There are? The only two I can think of are the left-biased and its dual, in which case the convention is to choose the left-biased one. Is there another? Luke