On Mon, 2006-08-28 at 20:11 -0700, Ted Kremenek wrote:

> While the structural typing in Ocaml is wonderful (I really love it),  
> there are missing features of the OO system in OCaml that can be  
> particularly bothersome, and are worth considering when comparing the  
> OO features of Ocaml with other languages (including those that use  
> nominal typing).
> 
> For example, from what I can tell it appears that Ocaml lacks real  
> support for "downcasts" in the language, which require run-time type  
> information (RTTI) and run-time checks.

Yes, indeed, this is wonderful! For the first time programmers
learn the truth.

Ocaml does not pander to the false god of Object Orientation.

>   In the context of structural  
> typing, I am talking about "casting" an object with a type with a  
> given set of method signatures to another type with an extended set  
> of method signatures. 

There is no need. Use the proper technology: variants.

They provide run time type information on which you can
dispatch.


-- 
John Skaller <skaller at users dot sf dot net>
Felix, successor to C++: http://felix.sf.net