diff --git a/include/boost/variant2/expected.hpp b/include/boost/variant2/expected.hpp index 4673ab5..87022e8 100644 --- a/include/boost/variant2/expected.hpp +++ b/include/boost/variant2/expected.hpp @@ -78,17 +78,10 @@ private: public: explicit bad_expected_access( E const& e ) - noexcept( std::is_nothrow_copy_constructible::value ) : bad_expected_access( "bad_expected_access<" + boost::core::demangle( typeid(E).name() ) + ">" + variant2::detail::add_value( e ) ), e_( e ) { } - explicit bad_expected_access( E&& e ) - noexcept( std::is_nothrow_move_constructible::value ) - : bad_expected_access( "bad_expected_access<" + boost::core::demangle( typeid(E).name() ) + ">" + variant2::detail::add_value( e ) ), e_( std::move(e) ) - { - } - E error() const { return e_; @@ -377,7 +370,7 @@ public: return mp_with_index>( v_.index(), [&]( auto I ) { - return _remap_error( I, f, get(v_) ); + return this->_remap_error( I, f, get(v_) ); }); } @@ -390,7 +383,7 @@ public: return mp_with_index>( v_.index(), [&]( auto I ) { - return _remap_error( I, f, get(v_) ); + return this->_remap_error( I, f, get(v_) ); }); } @@ -416,6 +409,18 @@ public: return unexpected(); } } + + template then_result operator>>( F && f ) const + { + if( has_value() ) + { + return std::forward(f)( **this ); + } + else + { + return unexpected(); + } + } }; template inline constexpr bool operator==( expected const & x1, expected const & x2 ) diff --git a/include/boost/variant2/variant.hpp b/include/boost/variant2/variant.hpp index cb669ad..4a0937c 100644 --- a/include/boost/variant2/variant.hpp +++ b/include/boost/variant2/variant.hpp @@ -112,7 +112,7 @@ template constexpr bool holds_alternative( variant co return v.index() == mp_find, U>::value; } -// get +// get (index) template constexpr variant_alternative_t>& get(variant& v) { @@ -178,7 +178,7 @@ template constexpr variant_alternative_t constexpr U& get(variant& v) { @@ -253,13 +253,13 @@ template constexpr U const&& get(variant const&& v) template constexpr std::add_pointer_t>> get_if(variant* v) noexcept { static_assert( I < sizeof...(T), "Index out of bounds" ); - return v->index() == I? &v->_get_impl( mp_size_t() ): 0; + return v && v->index() == I? &v->_get_impl( mp_size_t() ): 0; } template constexpr std::add_pointer_t>> get_if(variant const * v) noexcept { static_assert( I < sizeof...(T), "Index out of bounds" ); - return v->index() == I? &v->_get_impl( mp_size_t() ): 0; + return v && v->index() == I? &v->_get_impl( mp_size_t() ): 0; } template constexpr std::add_pointer_t get_if(variant* v) noexcept @@ -267,7 +267,7 @@ template constexpr std::add_pointer_t get_if(variant, U>::value == 1, "The type must occur exactly once in the list of variant alternatives" ); constexpr auto I = mp_find, U>::value; - return v->index() == I? &v->_get_impl( mp_size_t() ): 0; + return v && v->index() == I? &v->_get_impl( mp_size_t() ): 0; } template constexpr std::add_pointer_t get_if(variant const * v) noexcept @@ -275,7 +275,7 @@ template constexpr std::add_pointer_t get_if(varia static_assert( mp_count, U>::value == 1, "The type must occur exactly once in the list of variant alternatives" ); constexpr auto I = mp_find, U>::value; - return v->index() == I? &v->_get_impl( mp_size_t() ): 0; + return v && v->index() == I? &v->_get_impl( mp_size_t() ): 0; } // @@ -1064,7 +1064,7 @@ public: using J = mp_find, mp_at_c, I>>; - return _subset_impl( J{}, this->_get_impl( I ) ); + return this->_subset_impl( J{}, this->_get_impl( I ) ); }); } @@ -1077,7 +1077,7 @@ public: using J = mp_find, mp_at_c, I>>; - return _subset_impl( J{}, this->_get_impl( I ) ); + return this->_subset_impl( J{}, this->_get_impl( I ) ); }); } @@ -1090,7 +1090,7 @@ public: using J = mp_find, mp_at_c, I>>; - return _subset_impl( J{}, std::move( this->_get_impl( I ) ) ); + return this->_subset_impl( J{}, std::move( this->_get_impl( I ) ) ); }); } @@ -1103,7 +1103,7 @@ public: using J = mp_find, mp_at_c, I>>; - return _subset_impl( J{}, std::move( this->_get_impl( I ) ) ); + return this->_subset_impl( J{}, std::move( this->_get_impl( I ) ) ); }); } diff --git a/test/Jamfile b/test/Jamfile index 3dccee1..c11eef5 100644 --- a/test/Jamfile +++ b/test/Jamfile @@ -39,3 +39,5 @@ run variant_eq_ne.cpp : : : $(REQ) ; run variant_destroy.cpp : : : $(REQ) ; run variant_visit.cpp : : : $(REQ) ; run variant_lt_gt.cpp : : : $(REQ) ; +run variant_convert_construct.cpp : : : $(REQ) ; +run variant_subset.cpp : : : $(REQ) ; diff --git a/test/variant_convert_construct.cpp b/test/variant_convert_construct.cpp new file mode 100644 index 0000000..dbf61d9 --- /dev/null +++ b/test/variant_convert_construct.cpp @@ -0,0 +1,175 @@ + +// Copyright 2017 Peter Dimov. +// +// Distributed under the Boost Software License, Version 1.0. +// +// See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt + +#include +#include +#include +#include +#include +#include + +using namespace boost::variant2; + +#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__) + +struct X1 +{ + int v; + + X1(): v(0) {} + explicit X1(int v): v(v) {} + X1(X1 const& r): v(r.v) {} + X1(X1&& r): v(r.v) {} + X1& operator=( X1 const& r ) { v = r.v; return *this; } + X1& operator=( X1&& r ) { v = r.v; return *this; } +}; + +inline bool operator==( X1 const& a, X1 const& b ) { return a.v == b.v; } + +STATIC_ASSERT( !std::is_nothrow_default_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_move_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_assignable::value ); +STATIC_ASSERT( !std::is_nothrow_move_assignable::value ); + +struct X2 +{ + int v; + + X2(): v(0) {} + explicit X2(int v): v(v) {} + X2(X2 const& r): v(r.v) {} + X2(X2&& r): v(r.v) {} + X2& operator=( X2 const& r ) { v = r.v; return *this; } + X2& operator=( X2&& r ) { v = r.v; return *this; } +}; + +inline bool operator==( X2 const& a, X2 const& b ) { return a.v == b.v; } + +STATIC_ASSERT( !std::is_nothrow_default_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_move_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_assignable::value ); +STATIC_ASSERT( !std::is_nothrow_move_assignable::value ); + +int main() +{ + { + variant v( 1 ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant const v( 1 ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v( 1 ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant const v( 1 ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v( 3.14f ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v( 3.15f ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v( "s1" ); + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ), get( v2 ) ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v{ X1{1} }; + + variant v2( v ); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v ).v, get( v2 ).v ); + + variant v3( std::move(v) ); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ).v, get( v3 ).v ); + } + + return boost::report_errors(); +} diff --git a/test/variant_get_by_index.cpp b/test/variant_get_by_index.cpp index b55313e..950e73a 100644 --- a/test/variant_get_by_index.cpp +++ b/test/variant_get_by_index.cpp @@ -196,5 +196,55 @@ int main() BOOST_TEST_EQ( get<2>(std::move(v)), 3.14f ); } + { + variant * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if<0>(p), nullptr ); + } + return boost::report_errors(); } diff --git a/test/variant_get_by_type.cpp b/test/variant_get_by_type.cpp index 82b18c7..5a179dc 100644 --- a/test/variant_get_by_type.cpp +++ b/test/variant_get_by_type.cpp @@ -162,5 +162,49 @@ int main() BOOST_TEST_EQ( get_if(&v), &get(v) ); } + { + variant * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant * p = 0; + + BOOST_TEST_EQ( get_if(p), nullptr ); + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant const * p = 0; + + BOOST_TEST_EQ( get_if(p), nullptr ); + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + + { + variant const * p = 0; + BOOST_TEST_EQ( get_if(p), nullptr ); + } + return boost::report_errors(); } diff --git a/test/variant_subset.cpp b/test/variant_subset.cpp new file mode 100644 index 0000000..86cd505 --- /dev/null +++ b/test/variant_subset.cpp @@ -0,0 +1,155 @@ + +// Copyright 2017 Peter Dimov. +// +// Distributed under the Boost Software License, Version 1.0. +// +// See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt + +#include +#include +#include +#include +#include +#include + +using namespace boost::variant2; + +#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__) + +struct X1 +{ + int v; + + X1(): v(0) {} + explicit X1(int v): v(v) {} + X1(X1 const& r): v(r.v) {} + X1(X1&& r): v(r.v) {} + X1& operator=( X1 const& r ) { v = r.v; return *this; } + X1& operator=( X1&& r ) { v = r.v; return *this; } +}; + +inline bool operator==( X1 const& a, X1 const& b ) { return a.v == b.v; } + +STATIC_ASSERT( !std::is_nothrow_default_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_move_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_assignable::value ); +STATIC_ASSERT( !std::is_nothrow_move_assignable::value ); + +struct X2 +{ + int v; + + X2(): v(0) {} + explicit X2(int v): v(v) {} + X2(X2 const& r): v(r.v) {} + X2(X2&& r): v(r.v) {} + X2& operator=( X2 const& r ) { v = r.v; return *this; } + X2& operator=( X2&& r ) { v = r.v; return *this; } +}; + +inline bool operator==( X2 const& a, X2 const& b ) { return a.v == b.v; } + +STATIC_ASSERT( !std::is_nothrow_default_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_move_constructible::value ); +STATIC_ASSERT( !std::is_nothrow_copy_assignable::value ); +STATIC_ASSERT( !std::is_nothrow_move_assignable::value ); + +int main() +{ + { + variant v1( 1 ); + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ), get( v2 ) ); + + BOOST_TEST_THROWS( v1.subset(), bad_variant_access ); + + variant v3 = std::move(v1).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + + BOOST_TEST_THROWS( std::move(v1).subset(), bad_variant_access ); + } + + { + variant const v1( 1 ); + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ), get( v2 ) ); + + BOOST_TEST_THROWS( v1.subset(), bad_variant_access ); + + variant v3 = std::move(v1).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + + BOOST_TEST_THROWS( std::move(v1).subset(), bad_variant_access ); + } + + { + variant v1( 1 ); + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ), get( v2 ) ); + + variant v3 = std::move(v1).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v1( 1 ); + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ), get( v2 ) ); + + variant v3 = std::move(v1).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v1( "s1" ); + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ), get( v2 ) ); + + variant v3 = std::move(v1).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ), get( v3 ) ); + } + + { + variant v1{ X1{1} }; + + variant v2 = v1.subset(); + + BOOST_TEST( holds_alternative( v2 ) ); + BOOST_TEST_EQ( get( v1 ).v, get( v2 ).v ); + + variant v3 = std::move( v1 ).subset(); + + BOOST_TEST( holds_alternative( v3 ) ); + BOOST_TEST_EQ( get( v2 ).v, get( v3 ).v ); + } + + return boost::report_errors(); +}