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From: "Nicolas Cannasse" <warplayer@free.fr>
To: "Pierre Weis" <pierre.weis@inria.fr>,
        "Falk Hueffner" <falk.hueffner@student.uni-tuebingen.de>
Cc: <caml-list@inria.fr>
References: <200312171914.UAA00389@pauillac.inria.fr>
Subject: Re: [Caml-list] Python's yield, Lisp's call-cc or C's setjmp/longjmp in OCaml
Date: Thu, 18 Dec 2003 10:14:19 +0900
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> [...]
> > This only works for simple examples. Try for example writing a
> > function which successively yields all possible moves for a chess
> > board. The "yield" operator really helps there.
>
> Very interesting: please give us the code corresponding to this
> example, in order for us to realize how the full power of the "yield"
> operator helps to solve this problem.
>
> Pierre Weis
>

One simple sample is tree walking :
"if there was yield in ocaml"

type 'a tree =
    |  Node of 'a tree list
    |  Leaf of 'a

let rec iterator = function
    | Node l -> List.iter iterator l
    | Leaf x -> yield x

Doing it using a closure is more difficult, since we need to reproduce the
stack using a data structure. That goes of course for all recursive data
structures.

Nicolas Cannasse

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