ceph/src/boost/libs/parameter/test/literate/extracting-parameter-types0.cpp

   1
   2 #include <boost/parameter.hpp>
   3
   4 BOOST_PARAMETER_NAME(name)
   5 BOOST_PARAMETER_NAME(index)
   6
   7 template <typename T>
   8 #if defined(BOOST_PARAMETER_HAS_PERFECT_FORWARDING)
   9 void noop(T&&)
  10 #else
  11 void noop(T&)
  12 #endif
  13 {
  14 }
  15
  16 #if defined(BOOST_PARAMETER_HAS_PERFECT_FORWARDING)
  17 #include <utility>
  18 #endif
  19
  20 template <typename Name, typename Index>
  21 #if defined(BOOST_PARAMETER_HAS_PERFECT_FORWARDING)
  22 int deduce_arg_types_impl(Name&& name, Index&& index)
  23 {
  24     noop(std::forward<Name>(name));
  25     noop(std::forward<Index>(index));
  26     return index;
  27 }
  28 #else
  29 int deduce_arg_types_impl(Name& name, Index& index)
  30 {
  31     Name& n2 = name;  // we know the types
  32     Index& i2 = index;
  33     noop(n2);
  34     noop(i2);
  35     return index;
  36 }
  37 #endif
  38
  39 template <typename ArgumentPack>
  40 int deduce_arg_types(ArgumentPack const& args)
  41 {
  42     return deduce_arg_types_impl(args[_name], args[_index|42]);
  43 }
  44
  45 #include <boost/core/lightweight_test.hpp>
  46
  47 int main()
  48 {
  49     int a1 = deduce_arg_types((_name = "foo"));
  50     int a2 = deduce_arg_types((_name = "foo", _index = 3));
  51     BOOST_TEST_EQ(a1, 42);
  52     BOOST_TEST_EQ(a2, 3);
  53     return boost::report_errors();
  54 }
  55