ceph/src/boost/libs/parameter/test/literate/building-argumentpacks0.cpp

   1
   2 #include <boost/parameter.hpp>
   3 #include <iostream>
   4
   5 BOOST_PARAMETER_NAME(index)
   6
   7 template <typename ArgumentPack>
   8 int print_index(ArgumentPack const& args)
   9 {
  10     std::cout << "index = " << args[_index] << std::endl;
  11     return 0;
  12 }
  13
  14 BOOST_PARAMETER_NAME(name)
  15
  16 template <typename ArgumentPack>
  17 int print_name_and_index(ArgumentPack const& args)
  18 {
  19     std::cout << "name = " << args[_name] << "; ";
  20     return print_index(args);
  21 }
  22
  23 #include <boost/core/lightweight_test.hpp>
  24 #include <boost/mpl/bool.hpp>
  25 #include <boost/mpl/placeholders.hpp>
  26 #include <boost/mpl/if.hpp>
  27 #include <boost/type_traits/is_convertible.hpp>
  28
  29 int main()
  30 {
  31     int x = print_index(_index = 3);  // prints "index = 3"
  32     int y = print_name_and_index((_index = 3, _name = "jones"));
  33     boost::parameter::parameters<
  34         boost::parameter::required<
  35             tag::name
  36           , boost::mpl::if_<
  37                 boost::is_convertible<boost::mpl::_,char const*>
  38               , boost::mpl::true_
  39               , boost::mpl::false_
  40             >
  41         >
  42       , boost::parameter::optional<
  43             tag::index
  44           , boost::mpl::if_<
  45                 boost::is_convertible<boost::mpl::_,int>
  46               , boost::mpl::true_
  47               , boost::mpl::false_
  48             >
  49         >
  50     > spec;
  51     char const sam[] = "sam";
  52     int twelve = 12;
  53     int z0 = print_name_and_index(spec(sam, twelve));
  54     int z1 = print_name_and_index(spec(_index=12, _name="sam"));
  55     BOOST_TEST(!x);
  56     BOOST_TEST(!y);
  57     BOOST_TEST(!z0);
  58     BOOST_TEST(!z1);
  59     return boost::report_errors();
  60 }
  61