Re: [boost] Boost.Multimethod proposal

Subject: Re: [boost] Boost.Multimethod proposal
From: Larry Evans (cppljevans_at_[hidden])
Date: 2009-08-22 21:58:39

On 08/21/09 17:28, Nicholas Howe wrote:
> I have written a C++ Multimethod library and propose adding it to Boost. 
[snip]

> The library works by requiring clients to register user types of interest,
> and specify their public base classes.  This allows traversing class
> hierarchies at run-time.  A multimethod uses this information to perform
> run-time overload resolution on registered methods to determine the best
> implementation based on the type-id of each parameter.  There are no
> restrictions on the types of a multimethod's parameters, although only
> single indirections to user types will behave polymorphically.
[snip]

Hi Nicholas,

I haven't looked at your code, but the mention of "registered methods"
in the above quote suggests some sort of time consuming lookup.

I just uploaded to boost_vault/Patterns a text file:

   PescioNdispatch.txt

This was written years about (aroung 2003) so I can't remember
very well the details, but, IIRC, it uses some sort fo elaborate
multiple inheiritance and maybe some casting to achieve the dispatch,
but I think it just uses virtual methods.

Anyway, it might be worth comparing with your method.

-regards,
Larry