// // Copyright 2003 © The Trustees of Indiana University. All rights // reserved. // // See the file enable_if_LICENSE for licensing conditions. // // Authors: Jaakko Järvi (jajarvi@osl.iu.edu) // Jeremiah Willcock (jewillco@osl.iu.edu) // Andrew Lumsdaine (lums@osl.iu.edu) // #include #include #include #include using boost::lazy_enable_if; using boost::lazy_disable_if; using boost::lazy_enable_if_c; using boost::lazy_disable_if_c; using boost::is_arithmetic; template struct some_traits { BOOST_STATIC_CONSTANT(bool, value = false); }; template <> struct some_traits { BOOST_STATIC_CONSTANT(bool, value = true); typedef bool type; }; template <> struct some_traits { BOOST_STATIC_CONSTANT(bool, value = true); typedef bool type; }; template struct make_bool { typedef bool type; }; template <> struct make_bool {}; template <> struct make_bool {}; namespace A { template typename lazy_enable_if, some_traits >::type foo(T t) { return true; } template typename lazy_enable_if_c::value, some_traits >::type foo2(T t) { return true; } } namespace B { template typename lazy_disable_if, make_bool >::type foo(T t) { return false; } template typename lazy_disable_if_c::value, make_bool >::type foo2(T t) { return false; } } int test_main(int, char*[]) { using namespace A; using namespace B; BOOST_TEST(foo(1)); BOOST_TEST(foo(1.0)); BOOST_TEST(!foo("1")); BOOST_TEST(!foo(static_cast(0))); BOOST_TEST(foo2(1)); BOOST_TEST(foo2(1.0)); BOOST_TEST(!foo2("1")); BOOST_TEST(!foo2(static_cast(0))); return 0; }