pjb3/foldr.clj

Created April 17, 2009 04:43

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	(defn foldr [f acc coll]
	(if (first coll)
	(f (first coll) (foldr f acc (rest coll)))
	[]))

gnn commented Jan 13, 2011

Stumbled upon this after googling "clojure foldr". I realise this gist is quite old, so I apologise in advance if you feel this is pointless.
The last line should be:

acc))

Bill commented Aug 13, 2017

With the change, it is a right-associative fold:

(foldr list () (range 3))
=> (0 (1 (2 ())))

But it isn't lazy like Haskell fold:

(take 2 (foldr list () (range)))

StackOverflowError   clojure.lang.RT.first (RT.java:682)

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