Re: forward function definitions

[Sven LUTHER <luther@maxime.u-strasbg.fr>]

On Wed, Jun 09, 1999 at 02:38:22PM -0400, Junbiao Zhang wrote:
> Hi,
> 
> 	We're developing a fairly large system with multiple function
> definitions. It's inevitable that some functions may call other functions
> defined later(may not even be recursive calls as in the case of
> Sys.Signal_handle). My question is: how do I solve such a problem which is
> extremely trival in other languages?  Thanks. 

If the two functions are in different modules, just provide a interface file
for them, and it should work ok but can cause some linker problems.

2 clean way of doing this are :

* use the later called function as a parameter to the first called function :

  let register_signals_arg f =  Sys.signal Sys.sigalrm (Sys.Signal_handle f)

  ...
  
  let a sigid = ...
  let register_signals = register_signals_arg a
  
* Or you could define all this in the form of a module functor :

  module type XXX = sig val a : id -> ... end
  module Make_M (X : XXX) = struct
    let register_signals =  Sys.signal Sys.sigalrm (Sys.Signal_handle X.a)
	 end
  module ARG = struct 
    let a sigid = ...
	 end
  module M = Make_M ARG
  open M
	
Friendly,

Sven LUTHER