Re: [Caml-list] How to do this properly with OCaml?

[Berke Durak <obdurak@free.fr>]

On Sat, Jul 23, 2005 at 02:34:03PM +0200, Xavier Leroy wrote:
> > I was constructing a binary heap of tuples the other day.  After pondering
> > these options, I just used Obj.magic 0 as the null value in the array.
> > The heap was in a module, so nothing else could see the array, and I could
> > prove that the code never accessed the null elements, so the use of
> > Obj.magic seemed justified.
> 
> In other terms:
> 
> " I was walking in the city the other day.  I saw a syringe lying on
>   the sidewalk.  I stuck the needle in my forearm.  That was a classy
>   neighborhood, so the use of the syringe seemed justified. "

Quite a metaphor.

However I was wondering how feasible it would be to have a "any : 'a"
value, that would return an (unspecified) value of any given type...
This is clearly feasible for base types.  Hence it should also be possible
for tuples, records and functions of base types.  Recursive values could
prove problematic :

  type stuff1 = { mutable a : stuff2 }
  and stuff2 = { mutable b : stuff1 }
  
Would it be worth the fuss ?
-- 
Berke Durak