1
2// Copyright 2017 Peter Dimov.
3//
4// Distributed under the Boost Software License, Version 1.0.
5//
6// See accompanying file LICENSE_1_0.txt or copy at
7// http://www.boost.org/LICENSE_1_0.txt
8
9#if defined(_MSC_VER)
10# pragma warning( disable: 4244 ) // conversion from float to int, possible loss of data
11#endif
12
13#include <boost/variant2/variant.hpp>
14#include <boost/mp11.hpp>
15#include <boost/core/lightweight_test.hpp>
16#include <boost/core/lightweight_test_trait.hpp>
17#include <boost/config.hpp>
18#include <type_traits>
19#include <utility>
20#include <string>
21#include <cstdio>
22
23using namespace boost::variant2;
24using boost::mp11::mp_size_t;
25
26struct X
27{
28};
29
30struct F
31{
32 mp_size_t<1> operator()( X& ) const;
33 mp_size_t<2> operator()( X const& ) const;
34 mp_size_t<3> operator()( X&& ) const;
35 mp_size_t<4> operator()( X const&& ) const;
36};
37
38int main()
39{
40 {
41 BOOST_TEST_EQ( (visit( []{ return 5; } )), 5 );
42 }
43
44 {
45 variant<int> v( 1 );
46
47 BOOST_TEST_EQ( (visit( []( int x ){ return x; }, v )), 1 );
48
49 visit( f: []( int x ){ BOOST_TEST_EQ( x, 1 ); }, v1&: v );
50 visit( f: []( int x ){ BOOST_TEST_EQ( x, 1 ); }, v1: std::move(v) );
51 }
52
53 {
54 variant<int> const v( 2 );
55
56 BOOST_TEST_EQ( (visit( []( int x ){ return x; }, v )), 2 );
57
58 visit( f: []( int x ){ BOOST_TEST_EQ( x, 2 ); }, v1: v );
59 visit( f: []( int x ){ BOOST_TEST_EQ( x, 2 ); }, v1: std::move(v) );
60 }
61
62 {
63 variant<int const> v( 3 );
64
65 BOOST_TEST_EQ( (visit( []( int x ){ return x; }, v )), 3 );
66
67 visit( f: []( int x ){ BOOST_TEST_EQ( x, 3 ); }, v1&: v );
68 visit( f: []( int x ){ BOOST_TEST_EQ( x, 3 ); }, v1: std::move(v) );
69 }
70
71 {
72 variant<int const> const v( 4 );
73
74 BOOST_TEST_EQ( (visit( []( int x ){ return x; }, v )), 4 );
75
76 visit( f: []( int x ){ BOOST_TEST_EQ( x, 4 ); }, v1: v );
77 visit( f: []( int x ){ BOOST_TEST_EQ( x, 4 ); }, v1: std::move(v) );
78 }
79
80 {
81 variant<int, float> v1( 1 );
82 variant<int, float> const v2( 3.14f );
83
84 BOOST_TEST_EQ( (visit( []( int x1, float x2 ){ return (int)(x1 * 1000) + (int)(x2 * 100); }, v1, v2 )), 1314 );
85
86 visit( f: []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, v1, v2 );
87 visit( f: []( int x1, float x2 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); }, v1: std::move(v1), v2: std::move(v2) );
88 }
89
90 {
91 variant<int, float, double> v1( 1 );
92 variant<int, float, double> const v2( 3.14f );
93 variant<int, float, double> v3( 6.28 );
94
95 BOOST_TEST_EQ( (visit( []( int x1, float x2, double x3 ){ return (int)(x1 * 100) * 1000000 + (int)(x2 * 100) * 1000 + (int)(x3 * 100); }, v1, v2, v3 )), 100314628 );
96
97 visit( f: []( int x1, float x2, double x3 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); BOOST_TEST_EQ( x3, 6.28 ); }, v1, v2, v&: v3 );
98 visit( f: []( int x1, float x2, double x3 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); BOOST_TEST_EQ( x3, 6.28 ); }, v1: std::move(v1), v2: std::move(v2), v: std::move(v3) );
99 }
100
101 {
102 variant<int, float, double, char> v1( 1 );
103 variant<int, float, double, char> const v2( 3.14f );
104 variant<int, float, double, char> v3( 6.28 );
105 variant<int, float, double, char> const v4( 'A' );
106
107 BOOST_TEST_EQ( (visit( []( int x1, float x2, double x3, char x4 ){ return (long long)(x1 * 100) * 100000000 + (long long)(x2 * 100) * 100000 + (long long)(x3 * 10000) + (int)x4; }, v1, v2, v3, v4 )), 10031462800 + 'A' );
108
109 visit( f: []( int x1, float x2, double x3, char x4 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); BOOST_TEST_EQ( x3, 6.28 ); BOOST_TEST_EQ( x4, 'A' ); }, v1, v2, v&: v3, v: v4 );
110 visit( f: []( int x1, float x2, double x3, char x4 ){ BOOST_TEST_EQ( x1, 1 ); BOOST_TEST_EQ( x2, 3.14f ); BOOST_TEST_EQ( x3, 6.28 ); BOOST_TEST_EQ( x4, 'A' ); }, v1: std::move(v1), v2: std::move(v2), v: std::move(v3), v: std::move(v4) );
111 }
112
113 {
114 variant<X> v;
115 variant<X> const cv;
116
117 BOOST_TEST_EQ( decltype(visit(F{}, v))::value, 1 );
118 BOOST_TEST_EQ( decltype(visit(F{}, cv))::value, 2 );
119 BOOST_TEST_EQ( decltype(visit(F{}, std::move(v)))::value, 3 );
120
121#if !BOOST_WORKAROUND(BOOST_GCC, < 40900)
122
123 // g++ 4.8 doesn't handle const&& particularly well
124 BOOST_TEST_EQ( decltype(visit(F{}, std::move(cv)))::value, 4 );
125
126#endif
127 }
128
129 return boost::report_errors();
130}
131

source code of boost/libs/variant2/test/variant_visit.cpp