Created
March 28, 2017 20:53
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Landin's Knot
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| (** "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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