[Haskell-beginners] Unmaybe

[Karol Samborski]

fromMaybe mempty

--
Karol Samborski

2013/5/14 Mats Rauhala <mats.rauhala at gmail.com>

> maybe mempty id
>
> On Tue, May 14, 2013 at 05:21:44PM +0800, Adrian May wrote:
> > Hi there,
> >
> > I have a really annoying scrap of code:
> >
> > unmaybe Nothing = mempty
> > unmaybe (Just dia) = dia
> >
> > It happened because I'm using Diagrams but building my diagram requires
> > looking something up in a list using findIndex, which returns Maybe Int.
> >
> > How do I rid myself of this blotch?
> >
> > TIA,
> > Adrian.
>
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>
>
> --
> Mats Rauhala
> MasseR
>
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