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[Caml-list] Memoizing (was: static variables...)

Benedikt Rosenau
- William Lovas
  - Christopher Quinn
    - Remi VANICAT
      - Christopher Quinn
  - Jacek Chrzaszcz
    - William Lovas
  - John Max Skaller
    - Pierre Weis

Date:	-- (:)
From:	John Max Skaller <skaller@o...>
Subject:	Re: [Caml-list] Memoizing (was: static variables...)

William Lovas wrote:

>
>    let recfib recfib = function
>      | 0 | 1 -> 1
>      | n -> recfib (n-1) + recfib (n-2);;
>

>
>Does anyone have any thoughts on this?  Am i missing something obvious?
>

let fib = ref (function | _ -> 1);;
fib := function  | 0 | 1 -> 1 | n-> !fib (n-1) + !fib (n-2) ;;
let memo h f x = (if not (Hashtbl.mem h x) then Hashtbl.add h  x (f x); 
Hashtbl.find h x);;
let h = Hashtbl.create 97;;
fib := memo h !fib;;



-- 
John Max Skaller, mailto:skaller@ozemail.com.au
snail:10/1 Toxteth Rd, Glebe, NSW 2037, Australia.
voice:61-2-9660-0850




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