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From: Danil Shopyrin (Danil.Shopyrin_at_[hidden])
Date: 2004-09-28 11:13:51




From: Danil Shopyrin
Sent: Monday, September 27, 2004 11:13 AM
To: 'boost_at_[hidden]'
Subject: RE: Re: [boost] Re: MultiMethod/Visitor Interest



Hi! - it's a "preliminary" version of my solution.

The [maybe] complete version can be found at

And some of mentioned drawbacks are already eliminated.


Background. My solution is an "idealized" solution. It is stands as an

answer to question: "can multimethods be implemented in C++ using only

'good' programming techniques?" It is fully compile time and absolutely type

safe. And there is no of RTTI. This is an academic result. Moreover, this is

ready to practical use (I do it).


There is a big resource of flexibility. By reducing the 'type safety sugar'

this solution can be extended. Look on "Compilation in separate modules"

section. And so on.


I hope that the approach can be extended to met 'practical solution'

requirements. But this is a hard job to one person to produce consistent set

of these requirements.


However, I think that "clear" solution is also practical in many cases.


Further, about drawbacks:


1) Compile time. Yes, this solution is strongly compile time.

   But I think it is an advantage :-)


2) You are right. There is no "next_method". I was never think of them.


3) Intrusive. It is eliminated.


4) "distinguishes the first argument". It is eliminated.


5) Gnarly user code. Look at up-to-date "tiny use case" at



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