[Haskell-beginners] Disjunction

[Tony Morris]

On 10/12/10 10:02, Russ Abbott wrote:
> I recently was writing code long these lines.
>
> f x = p1 x || p2 x || ... || pn x
>
> I would have liked to write that in pointfree form but couldn't find a
> library function to do it.
>
> I created this.
>
> disj :: [a -> Bool] -> a -> Bool
> disj ps = (\x -> or $ map ($x) ps)
>
> disj2 p1 p2 = disj [p1, p2]
> disj3 p1 p2 p3 = disj [p1, p2]
> disj4 p1 p2 p3 p4 = disj [p1, p2]
> ...
>
> With that I can write my function as follows.
>
> f = disj pi p2 p3 ... pn
>
> Is there a standard way to do this?
> /
> -- Russ/
>
>
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>   
disj = fmap or . sequence

-- 
Tony Morris
http://tmorris.net/


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