Re: [Boost-Users] bind question

From: Peter Dimov (pdimov_at_[hidden])
Date: 2002-01-04 08:47:01

From: "Duane Murphy" <duanemurphy_at_[hidden]>
> Is there a syntax for making boost::bind bind to functions that are
templates?

No. The reason is that a function template is not a function. It is an
entity that can generate functions.

You can't pass the name of a function template as an argument.

> Here is an (extremally simplified) example that doesnt compile:
>
> #include <boost/bind.hpp>
>
> template < class Function >
> void f( Function func )
> {
>     func( 46 );
> }
>
> void g( int num )
> {
>     num++;
> }
>
> int main( void )
> {
>    boost::bind( f, g )();
>     boost::bind( f, _1 )( g );
>
>     return 0;
> }
>
> The two bind lines in main both get an error "call of non-function".
>
> Is there a way to make this work?

Yes, use a function object:

#include <boost/bind.hpp>

struct F
{
    template < class Function > void operator()( Function func )
    {
        func( 46 );
    }
} f;

void g( int num )
{
    num++;
}

int main( void )
{
    boost::bind<void>( f, g )();
    boost::bind<void>( f, _1 )( g );
    return 0;
}

--
Peter Dimov
Multi Media Ltd.