1 // Copyright Abel Sinkovics (abel@sinkovics.hu) 2015. 2 // Distributed under the Boost Software License, Version 1.0. 3 // (See accompanying file LICENSE_1_0.txt or copy at 4 // http://www.boost.org/LICENSE_1_0.txt) 5 6 #include <boost/metaparse/optional.hpp> 7 #include <boost/metaparse/string.hpp> 8 #include <boost/metaparse/lit_c.hpp> 9 #include <boost/metaparse/get_result.hpp> 10 #include <boost/metaparse/start.hpp> 11 12 #include <boost/mpl/assert.hpp> 13 #include <boost/mpl/equal_to.hpp> 14 #include <boost/mpl/char.hpp> 15 16 #include <boost/type_traits/is_same.hpp> 17 18 #include "test_case.hpp" 19 BOOST_METAPARSE_TEST_CASE(optional)20BOOST_METAPARSE_TEST_CASE(optional) 21 { 22 using boost::metaparse::optional; 23 using boost::metaparse::lit_c; 24 using boost::metaparse::string; 25 using boost::metaparse::get_result; 26 using boost::metaparse::start; 27 28 using boost::mpl::equal_to; 29 30 using boost::is_same; 31 32 typedef optional<lit_c<'x'>, double> optional_x; 33 34 // test_optional_parser_succeeds 35 BOOST_MPL_ASSERT(( 36 equal_to< 37 boost::mpl::char_<'x'>, 38 get_result<optional_x::apply<string<'x'>, start> >::type 39 > 40 )); 41 42 // test_optional_parser_fails 43 BOOST_MPL_ASSERT(( 44 is_same<double, get_result<optional_x::apply<string<'y'>, start> >::type> 45 )); 46 47 // test_optional_parser_default_value 48 BOOST_MPL_ASSERT(( 49 is_same< 50 void, 51 get_result<optional<lit_c<'x'> >::apply<string<'y'>, start> >::type 52 > 53 )); 54 } 55 56