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