On Sat, Apr 10, 2004 at 10:36:16PM +0100, Richard Jones wrote:
> 
> I have a function defined:
> 
>   let plot ?(labels = string_of_int) graph =
>     (* ... *)

I don't think I can directly address your problem as stated here, but I
have one or two observations that might be relevant:

 * I had to grapple with a similar issue in developing my ChartPak
   toolkit: how do you generate a string from an arbitrary data type?
   I decided on an architecture where each chart type is implemented as
   an OCaml module. That module transforms a data set into a collection
   of abstract graphical objects (by that I mean that their shapes and
   relative positions are defined, but their actual dimensions are not).
   This collection is passed to a renderer which creates the actual
   image.

   This approach is more complex internally and less dynamic than I
   would like, but it does make for an API that is both fairly simple
   to use and not too hard to extend (assuming you can compile OCaml 
   code).

 * Do you really need to handle arbitrary data types? You will certainly
   have floats, ints, and strings, but what else? Maybe you should focus
   on providing a simple interface for the most common data types.

 * BTW, what sort of application/library are you working on here? If it
   is much like mine (and is open source and intended for general
   distribution), maybe we should think about joining forces.


-- 
Matt Gushee                 When a nation follows the Way,
Englewood, Colorado, USA    Horses bear manure through
mgushee@havenrock.com           its fields;
http://www.havenrock.com/   When a nation ignores the Way,
                            Horses bear soldiers through
                                its streets.
                                
                            --Lao Tzu (Peter Merel, trans.)

-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners