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Merge branch 'feature/issue-26' into develop

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This commit is contained in:
Peter Dimov
2021-03-13 18:23:39 +02:00
parent 3ca95a65df f39a71ed2f
commit 3bc9a57c9b
3 changed files with 36 additions and 1 deletions
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2
include/boost/variant2/variant.hpp
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@ -1584,7 +1584,7 @@ public:
template<class U,
class Ud = typename std::decay<U>::type,
class E1 = typename std::enable_if< !std::is_same<Ud, variant>::value && !detail::is_in_place_index<Ud>::value && !detail::is_in_place_type<Ud>::value >::type,
class E1 = typename std::enable_if< !std::is_same<Ud, variant>::value && !std::is_base_of<variant, Ud>::value && !detail::is_in_place_index<Ud>::value && !detail::is_in_place_type<Ud>::value >::type,
class V = detail::resolve_overload_type<U&&, T...>,
class E2 = typename std::enable_if<std::is_constructible<V, U&&>::value>::type
>

2
test/Jamfile
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@ -119,3 +119,5 @@ run variant_visit_r.cpp : : :
<toolset>gcc,<target-os>windows:<variant>release
<toolset>gcc,<target-os>cygwin:<variant>release
;
compile variant_derived_construct.cpp ;

33
test/variant_derived_construct.cpp Normal file
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@ -0,0 +1,33 @@
// Copyright 2021 Peter Dimov.
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
#include <boost/variant2/variant.hpp>
using namespace boost::variant2;
template<class... T> class X: variant<T...>
{
using base = variant<T...>;
using base::base;
};
struct Y
{
Y( Y const& rhs ) = default;
template<class T> Y( T const& t )
{
t.bar();
}
};
int main()
{
using W = X<int, double, Y>;
W a( 1 );
W b( a );
(void)b;
}