ceph/src/boost/libs/variant2/test/variant_visit_derived.cpp

   1 // Copyright 2017, 2020 Peter Dimov.
   2 // Distributed under the Boost Software License, Version 1.0.
   3 // https://www.boost.org/LICENSE_1_0.txt
   4
   5 #if defined(_MSC_VER)
   6 # pragma warning( disable: 4244 ) // conversion from float to int, possible loss of data
   7 #endif
   8
   9 #include <boost/variant2/variant.hpp>
  10 #include <boost/core/lightweight_test.hpp>
  11 #include <boost/config.hpp>
  12 #include <boost/config/workaround.hpp>
  13 #include <utility>
  14
  15 struct X: boost::variant2::variant<int, float>
  16 {
  17 #if BOOST_WORKAROUND( BOOST_MSVC, < 1940 )
  18
  19     template<class T> explicit X( T&& t ): variant( std::forward<T>( t ) ) {};
  20
  21 #else
  22
  23     using variant::variant;
  24
  25 #endif
  26 };
  27
  28 template<class... T> struct Y: boost::variant2::variant<T...>
  29 {
  30     using boost::variant2::variant<T...>::variant;
  31 };
  32
  33 int main()
  34 {
  35     {
  36         X v1( 1 );
  37         X const v2( 3.14f );
  38
  39         BOOST_TEST_EQ( (visit( []( int x1, float x2 ){ return (int)(x1 * 1000) + (int)(x2 * 100); }, v1, v2 )), 1314 );
  40
  41         visit( []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, v1, v2 );
  42         visit( []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, std::move(v1), std::move(v2) );
  43     }
  44
  45     {
  46         Y<int, float> v1( 1 );
  47         Y<int, float> const v2( 3.14f );
  48
  49         BOOST_TEST_EQ( (visit( []( int x1, float x2 ){ return (int)(x1 * 1000) + (int)(x2 * 100); }, v1, v2 )), 1314 );
  50
  51         visit( []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, v1, v2 );
  52         visit( []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, std::move(v1), std::move(v2) );
  53     }
  54
  55     return boost::report_errors();
  56 }