That doesn't exactly make sense. You'd need two versions of that function in all likelihood - one left-biased and another right-biased.

Hi!

I have two functions:

```
foo :: a -> Maybe b
bar :: a -> Maybe c
```

From which I want to build a higher order function:

```
foobar :: a -> (a -> Maybe b) -> (a -> Maybe c) -> Either b c
```

The implementation I need is:

```
foobar x f g =
  case (f x) of
    Nothing -> g x
    Just y  -> Just y
```

I'm a bit surprised that looking at hoogle I don't find a built-in
solution for this quite common need for `Maybe` types (or perhaps for
any monad).

Am I looking in the wrong way? Does it exist a similar abstraction but
with a different shape?

Thanks in advance,

Marc Busqué
http://waiting-for-dev.github.io/about/

_______________________________________________
Haskell-Cafe mailing list
To (un)subscribe, modify options or view archives go to:
http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
Only members subscribed via the mailman list are allowed to post.

--



Vanessa McHale
Functional Compiler Engineer | Chicago, IL

Website: www.iohk.io
Twitter: @vamchale
PGP Key ID: 4209B7B5






This e-mail and any file transmitted with it are confidential and intended solely for the use of the recipient(s) to whom it is addressed. Dissemination, distribution, and/or copying of the transmission by anyone other than the intended recipient(s) is prohibited. If you have received this transmission in error please notify IOHK immediately and delete it from your system. E-mail transmissions cannot be guaranteed to be secure or error free. We do not accept liability for any loss, damage, or error arising from this transmission