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Fix issue #98

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This commit is contained in:
Andrzej Krzemienski
2021-11-20 02:00:30 +01:00
parent 21253ea63a
commit 7dd512a019
47 changed files with 198 additions and 72 deletions
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79
include/boost/optional/optional.hpp
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@ -1,5 +1,5 @@
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
// Copyright (C) 2014 - 2018 Andrzej Krzemienski.
// Copyright (C) 2014 - 2021 Andrzej Krzemienski.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -37,14 +37,18 @@
#include <boost/type.hpp>
#include <boost/type_traits/alignment_of.hpp>
#include <boost/type_traits/conditional.hpp>
#include <boost/type_traits/conjunction.hpp>
#include <boost/type_traits/disjunction.hpp>
#include <boost/type_traits/has_nothrow_constructor.hpp>
#include <boost/type_traits/type_with_alignment.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/decay.hpp>
#include <boost/type_traits/is_assignable.hpp>
#include <boost/type_traits/is_base_of.hpp>
#include <boost/type_traits/is_const.hpp>
#include <boost/type_traits/is_constructible.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/type_traits/is_lvalue_reference.hpp>
#include <boost/type_traits/is_nothrow_move_assignable.hpp>
#include <boost/type_traits/is_nothrow_move_constructible.hpp>
@ -781,7 +785,7 @@ class optional_base : public optional_tag
// definition of metafunction is_optional_val_init_candidate
template <typename U>
struct is_optional_related
struct is_optional_or_tag
: boost::conditional< boost::is_base_of<optional_detail::optional_tag, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
|| boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<U>::type, none_t>::value
|| boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<U>::type, in_place_init_t>::value
@ -789,14 +793,22 @@ struct is_optional_related
boost::true_type, boost::false_type>::type
{};
template <typename T, typename U>
struct has_dedicated_constructor
: boost::disjunction<is_optional_or_tag<U>, boost::is_same<T, BOOST_DEDUCED_TYPENAME boost::decay<U>::type> >
{};
template <typename U>
struct is_in_place_factory
: boost::disjunction< boost::is_base_of<boost::in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>,
boost::is_base_of<boost::typed_in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type> >
{};
#if !defined(BOOST_OPTIONAL_DETAIL_NO_IS_CONSTRUCTIBLE_TRAIT)
template <typename T, typename U>
struct is_convertible_to_T_or_factory
: boost::conditional< boost::is_base_of<boost::in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
|| boost::is_base_of<boost::typed_in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
|| (boost::is_constructible<T, U&&>::value && !boost::is_same<T, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value)
, boost::true_type, boost::false_type>::type
struct is_factory_or_constructible_to_T
: boost::disjunction< is_in_place_factory<U>, boost::is_constructible<T, U&&> >
{};
template <typename T, typename U>
@ -806,7 +818,7 @@ struct is_optional_constructible : boost::is_constructible<T, U>
#else
template <typename, typename>
struct is_convertible_to_T_or_factory : boost::true_type
struct is_factory_or_constructible_to_T : boost::true_type
{};
template <typename T, typename U>
@ -815,15 +827,58 @@ struct is_optional_constructible : boost::true_type
#endif // is_convertible condition
template <typename T, typename U, bool = is_optional_related<U>::value>
#if !defined(BOOST_NO_CXX11_DECLTYPE) && !BOOST_WORKAROUND(BOOST_MSVC, < 1800)
// for is_assignable
#if (!defined BOOST_NO_CXX11_RVALUE_REFERENCES)
// On some initial rvalue reference implementations GCC does it in a strange way,
// preferring perfect-forwarding constructor to implicit copy constructor.
template <typename T, typename U>
struct is_opt_assignable
: boost::conjunction<boost::is_convertible<U&&, T>, boost::is_assignable<T&, U&&> >
{};
#else
template <typename T, typename U>
struct is_opt_assignable
: boost::conjunction<boost::is_convertible<U, T>, boost::is_assignable<T&, U> >
{};
#endif
#else
template <typename T, typename U>
struct is_opt_assignable : boost::is_convertible<U, T>
{};
#endif
template <typename T, typename U>
struct is_factory_or_opt_assignable_to_T
: boost::disjunction< is_in_place_factory<U>, is_opt_assignable<T, U> >
{};
template <typename T, typename U, bool = has_dedicated_constructor<T, U>::value>
struct is_optional_val_init_candidate
: boost::false_type
{};
template <typename T, typename U>
struct is_optional_val_init_candidate<T, U, false>
: boost::conditional< is_convertible_to_T_or_factory<T, U>::value
, boost::true_type, boost::false_type>::type
: is_factory_or_constructible_to_T<T, U>
{};
template <typename T, typename U, bool = has_dedicated_constructor<T, U>::value>
struct is_optional_val_assign_candidate
: boost::false_type
{};
template <typename T, typename U>
struct is_optional_val_assign_candidate<T, U, false>
: is_factory_or_opt_assignable_to_T<T, U>
{};
} // namespace optional_detail
@ -996,7 +1051,7 @@ class optional
#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class Expr>
BOOST_DEDUCED_TYPENAME boost::enable_if<optional_detail::is_optional_val_init_candidate<T, Expr>, optional&>::type
BOOST_DEDUCED_TYPENAME boost::enable_if<optional_detail::is_optional_val_assign_candidate<T, Expr>, optional&>::type
operator= ( Expr&& expr )
{
this->assign_expr(boost::forward<Expr>(expr),boost::addressof(expr));