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henrytill/landins_knot.ml

Created March 28, 2017 20:53
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Landin's Knot
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landins_knot.ml
(** "Landin's Knot" - implements recursion by backpatching *)
let landins_knot f =
let r = ref (fun x -> assert false) in
let fixedpoint = f (fun x -> !r x) in
r := fixedpoint;
fixedpoint
let factorial =
let g f x =
if x = 0 then
1
else
x * f (x - 1)
in
landins_knot g
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