Re: [boost] more on boost::mem_fn

From: Peter Dimov (pdimov_at_[hidden])
Date: 2001-11-23 12:30:24

From: "Aleksey Gurtovoy" <alexy_at_[hidden]>
> We would love to, but besides educational issues there are also some
> technical problems :(. For example, the following code does not compiles
on
> MSVC6.5:
>
> #include "boost/bind.hpp"
> #include <string>
>
> struct something
> {
>     int id() const;
> };
>
> struct to_string
> {
>     typedef std::string result_type;
>     std::string operator()(int) const;
> };
>
> int main()
> {
>     something* s;
>     boost::bind(to_string(), boost::bind(&something::id, _1))(s);
>     return 0;
> }
>
> And AFAIK it should. The 'to_string()' function object is the main source
of
> troubles here. I haven't got time to look into details of what's happening
> here, though.

It should - and on a real compiler, it does. On MSVC, you need to use the
other syntax:

boost::bind<std::string>(to_string(), boost::bind(&something::id, _1))(s);

This looks like a good candidate for a FAQ entry.

--
Peter Dimov
Multi Media Ltd.