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Today's Topics:
1. Alternative (Imants Cekusins)
2. Re: Alternative (Oliver Charles)
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Message: 1
Date: Wed, 28 Dec 2016 11:55:06 +0100
From: Imants Cekusins <ima...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: [Haskell-beginners] Alternative
Message-ID:
<cap1qinarhu776do9ff7swtekvvi45dyokpskzgkxt8d0jhh...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
discovered this handy snippet today (duh :):
>>> foldl (<|>) Nothing [Nothing, Just 1, Nothing, Just 2]
Just 1
basically, pick first Just from a list of Maybes
http://hackage.haskell.org/package/base-4.9.0.0/docs/Control-Applicative.html#g:2
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Message: 2
Date: Wed, 28 Dec 2016 12:10:29 +0000
From: Oliver Charles <ol...@ocharles.org.uk>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Alternative
Message-ID:
<cagrp5rmksgape-pg4e2jvygttdvuu700ovezrrarnx9ggj2...@mail.gmail.com>
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If you want something even simpler:
asum [Nothing, Just True, Nothing, Just False]
>From Data.Foldable :)
On Wed, 28 Dec 2016, 10:56 am Imants Cekusins, <ima...@gmail.com> wrote:
> discovered this handy snippet today (duh :):
>
> >>> foldl (<|>) Nothing [Nothing, Just 1, Nothing, Just 2]
> Just 1
>
> basically, pick first Just from a list of Maybes
>
>
>
> http://hackage.haskell.org/package/base-4.9.0.0/docs/Control-Applicative.html#g:2
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
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