Re: [boost] [Ann] Variadic Templates

From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2006-08-07 16:11:21

Joe Gottman wrote:
> This looks very nice.  I hope the standards committee accepts it.  I do have 
> one question: is it possible to define a variadic function such that all the 
> variadic parameters are of the same type?  This would be useful, for 
> instance, to define a max() function that can finds the max value of any 
> number of parameters:
> 
> long x1, x2, x3, x4, x5;
> // Some code
> const long &max_x = max(x1, x2, x3, x4, x5);
> 
> If this is possible, would it be possible to define a variadic function 
> without making it a template function?

FWIW, you can do that today by providing an overload of std::mac_element:

template< class Rng >
range_iterator<Rng>::const_iterator max_element( const Rng& r )
{ return std::max_element( boost::begin(r), boost::end(r) ); }

const long& max = *max_element( 
boost::assign::ref_list_of(x1)(x2)(x3)(x4) );

-Thorsten