boost/algorithm/minmax.hpp

   1 //  (C) Copyright Herve Bronnimann 2004.
   2 //
   3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 /*
   7  Revision history:
   8    1 July 2004
   9       Split the code into two headers to lessen dependence on
  10       Boost.tuple. (Herve)
  11    26 June 2004
  12       Added the code for the boost minmax library. (Herve)
  13 */
  14
  15 #ifndef BOOST_ALGORITHM_MINMAX_HPP
  16 #define BOOST_ALGORITHM_MINMAX_HPP
  17
  18 /* PROPOSED STANDARD EXTENSIONS:
  19  *
  20  * minmax(a, b)
  21  * Effect: (b<a) ? std::make_pair(b,a) : std::make_pair(a,b);
  22  *
  23  * minmax(a, b, comp)
  24  * Effect: comp(b,a) ? std::make_pair(b,a) : std::make_pair(a,b);
  25  *
  26  */
  27
  28 #include <boost/tuple/tuple.hpp> // for using pairs with boost::cref
  29 #include <boost/ref.hpp>
  30
  31 namespace boost {
  32
  33   template <typename T>
  34   tuple< T const&, T const& >
  35   minmax(T const& a, T const& b) {
  36     return (b<a) ? make_tuple(cref(b),cref(a)) : make_tuple(cref(a),cref(b));
  37   }
  38
  39   template <typename T, class BinaryPredicate>
  40   tuple< T const&, T const& >
  41   minmax(T const& a, T const& b, BinaryPredicate comp) {
  42     return comp(b,a) ? make_tuple(cref(b),cref(a)) : make_tuple(cref(a),cref(b));
  43   }
  44
  45 } // namespace boost
  46
  47 #endif // BOOST_ALGORITHM_MINMAX_HPP