puffnfresh/F.hs

Created January 30, 2014 16:12

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This should fully specify reverse.

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F.hs

	-- \|
	-- prop> \xs -> f (f xs) == xs
	-- prop> \xs ys -> f ys ++ f xs == f (xs ++ ys)
	f :: [a] -> [a]
	f = foldl (flip (:)) []

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