Re: [Boost-users] [bind] Possible to use variadic templates with bind?

Steve Lorimer wrote:

Hi

Is it possible to pass variadic template arguments to bind, such that bind uses them as the placeholder arguments (_1, _2, _3 etc)

I show my use case below. ... template struct cb { typedef void (T::*type)(Args...); }; ... job_t(typename cb::type cb, boost::shared_ptr<T> that, boost::shared_ptr q) : arg_func(boost::bind(cb, that, Args...)), queue(q) {} // normally would be _1, _2, _3, etc

An interesting puzzle. I tried to apply the 'Indexes' technique shown in the bind implementation section of http://osl.iu.edu/~dgregor/cpp/variadic-templates.pdf and ended up with the following: #include #include template struct int_tuple {}; // make indexes impl is a helper for make indexes template struct make_indexes_impl; template struct make_indexes_impl, T, Types...> { typedef typename make_indexes_impl, Types...>::type type; }; template struct make_indexes_impl > { typedef int_tuple type; }; template struct make_indexes: make_indexes_impl<0, int_tuple<>, Types...> { }; template< class T, class... Args, int... Indexes > boost::function< void(Args...) > make_func_helper( void (T::* pm) (Args...), T * that, int_tuple< Indexes... > ) { return boost::bind( pm, that, boost::arg()... ); } template< class T, class... Args > boost::function< void(Args...) > make_func( void (T::* pm) (Args...), T * that ) { return make_func_helper( pm, that, typename make_indexes::type() ); } struct X { void f( int, int ) { } }; int main() { X x; boost::function f = make_func( &X::f, &x ); f( 1, 2 ); } Hope this helps.