[boost] Re: once again: boost.bind namespace conflicts and how to solvethem

From: Stefan Slapeta (stefan_nospam__at_[hidden])
Date: 2004-11-29 16:40:43

Peter Dimov wrote:

> 
> I'm really not sure what do you mean by "modern" boost requirements.
> 

None of the libraries that have recently been included into boost placed 
their headers in the boost root directory. I don't know whether this has 
become a (formal) requirement but that's what I wanted to express.

>> a) this header should be placed in the bind subdirectory, e.g.
>> boost/bind/bind.hpp
> 
> What purpose does that serve? Why not boost/bind/bind/bind.hpp?

It was just an idea how to separate this header from the existing. One 
of many possible.

> 
>> b) this header should introduce a separate namespace 'bind' or
>> 'function' to avoid the well-known namespace clashes with
>> boost::lambda that are _really_ annoying.
> 
> 
> Again, what purpose would that serve? The only name that bind.hpp 
> "reserves" in boost is 'bind'. Defining a namespace 'bind' still 
> reserves the same name in boost, namely, 'bind', except that user code 
> is now uglier.
> 

Try to include boost/bind.hpp and boost/lambda/bind.hpp at the same time 
(just for matters of uniformity: this is the first time where I don't 
agree that one of those includes is in a subdirectory and the other is not!)
I've not found any solution for how to use e.g. _1 from boost.lambda in 
one function and _1 from boost.bind in another _without_ having to 
qualify these two everytime, which is totally ugly IMO.

> 
> The original intent has been to make the placeholders globally 
> available. As identifiers that start with an underscore are not allowed 
> at the global namespace, and since defining a variable in a header would 
> cause link errors, the placeholders have been put in an unnamed namespace.

ah ... I understand. IIRC, the _1 from boost.lamba are types and don't 
have these problems therefore.
This means more or less that I'll never be able to write 'using 
boost::_1', no?

Stefan