| // Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal. |
| // Copyright (C) 2014 - 2018 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 |
| // http://www.boost.org/LICENSE_1_0.txt) |
| // |
| // See http://www.boost.org/libs/optional for documentation. |
| // |
| // You are welcome to contact the author at: |
| // fernando_cacciola@hotmail.com |
| // |
| // Revisions: |
| // 27 Apr 2008 (improved swap) Fernando Cacciola, Niels Dekker, Thorsten Ottosen |
| // 05 May 2014 (Added move semantics) Andrzej Krzemienski |
| // |
| #ifndef BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP |
| #define BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP |
| |
| #include <new> |
| #include <iosfwd> |
| |
| #ifdef BOOST_OPTIONAL_DETAIL_USE_STD_TYPE_TRAITS |
| # include <type_traits> |
| #endif |
| |
| #include <boost/assert.hpp> |
| #include <boost/core/addressof.hpp> |
| #include <boost/core/enable_if.hpp> |
| #include <boost/core/explicit_operator_bool.hpp> |
| #include <boost/core/swap.hpp> |
| #include <boost/optional/bad_optional_access.hpp> |
| #include <boost/static_assert.hpp> |
| #include <boost/throw_exception.hpp> |
| #include <boost/type.hpp> |
| #include <boost/type_traits/alignment_of.hpp> |
| #include <boost/type_traits/conditional.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_base_of.hpp> |
| #include <boost/type_traits/is_const.hpp> |
| #include <boost/type_traits/is_constructible.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> |
| #include <boost/type_traits/is_rvalue_reference.hpp> |
| #include <boost/type_traits/is_same.hpp> |
| #include <boost/type_traits/is_volatile.hpp> |
| #include <boost/type_traits/is_scalar.hpp> |
| #include <boost/move/utility.hpp> |
| #include <boost/none.hpp> |
| #include <boost/utility/compare_pointees.hpp> |
| #include <boost/utility/result_of.hpp> |
| |
| #include <boost/optional/optional_fwd.hpp> |
| #include <boost/optional/detail/optional_config.hpp> |
| #include <boost/optional/detail/optional_factory_support.hpp> |
| #include <boost/optional/detail/optional_aligned_storage.hpp> |
| |
| namespace boost { namespace optional_detail { |
| |
| template <typename T> |
| struct optional_value_type |
| { |
| }; |
| |
| template <typename T> |
| struct optional_value_type< ::boost::optional<T> > |
| { |
| typedef T type; |
| }; |
| |
| }} // namespace boost::optional_detail |
| |
| #ifdef BOOST_OPTIONAL_CONFIG_USE_OLD_IMPLEMENTATION_OF_OPTIONAL |
| #include <boost/optional/detail/old_optional_implementation.hpp> |
| #else |
| namespace boost { |
| |
| namespace optional_ns { |
| |
| // a tag for in-place initialization of contained value |
| struct in_place_init_t |
| { |
| struct init_tag{}; |
| explicit in_place_init_t(init_tag){} |
| }; |
| const in_place_init_t in_place_init ((in_place_init_t::init_tag())); |
| |
| // a tag for conditional in-place initialization of contained value |
| struct in_place_init_if_t |
| { |
| struct init_tag{}; |
| explicit in_place_init_if_t(init_tag){} |
| }; |
| const in_place_init_if_t in_place_init_if ((in_place_init_if_t::init_tag())); |
| |
| } // namespace optional_ns |
| |
| using optional_ns::in_place_init_t; |
| using optional_ns::in_place_init; |
| using optional_ns::in_place_init_if_t; |
| using optional_ns::in_place_init_if; |
| |
| namespace optional_detail { |
| |
| struct init_value_tag {}; |
| |
| struct optional_tag {}; |
| |
| |
| template<class T> |
| class optional_base : public optional_tag |
| { |
| private : |
| |
| typedef aligned_storage<T> storage_type ; |
| typedef optional_base<T> this_type ; |
| |
| protected : |
| |
| typedef T value_type ; |
| |
| protected: |
| typedef T & reference_type ; |
| typedef T const& reference_const_type ; |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| typedef T && rval_reference_type ; |
| typedef T && reference_type_of_temporary_wrapper ; |
| #endif |
| typedef T * pointer_type ; |
| typedef T const* pointer_const_type ; |
| typedef T const& argument_type ; |
| |
| // Creates an optional<T> uninitialized. |
| // No-throw |
| optional_base() |
| : |
| m_initialized(false) {} |
| |
| // Creates an optional<T> uninitialized. |
| // No-throw |
| optional_base ( none_t ) |
| : |
| m_initialized(false) {} |
| |
| // Creates an optional<T> initialized with 'val'. |
| // Can throw if T::T(T const&) does |
| optional_base ( init_value_tag, argument_type val ) |
| : |
| m_initialized(false) |
| { |
| construct(val); |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // move-construct an optional<T> initialized from an rvalue-ref to 'val'. |
| // Can throw if T::T(T&&) does |
| optional_base ( init_value_tag, rval_reference_type val ) |
| : |
| m_initialized(false) |
| { |
| construct( boost::move(val) ); |
| } |
| #endif |
| |
| // Creates an optional<T> initialized with 'val' IFF cond is true, otherwise creates an uninitialized optional<T>. |
| // Can throw if T::T(T const&) does |
| optional_base ( bool cond, argument_type val ) |
| : |
| m_initialized(false) |
| { |
| if ( cond ) |
| construct(val); |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Creates an optional<T> initialized with 'move(val)' IFF cond is true, otherwise creates an uninitialized optional<T>. |
| // Can throw if T::T(T &&) does |
| optional_base ( bool cond, rval_reference_type val ) |
| : |
| m_initialized(false) |
| { |
| if ( cond ) |
| construct(boost::move(val)); |
| } |
| #endif |
| |
| // Creates a deep copy of another optional<T> |
| // Can throw if T::T(T const&) does |
| optional_base ( optional_base const& rhs ) |
| : |
| m_initialized(false) |
| { |
| if ( rhs.is_initialized() ) |
| construct(rhs.get_impl()); |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Creates a deep move of another optional<T> |
| // Can throw if T::T(T&&) does |
| optional_base ( optional_base&& rhs ) |
| BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value) |
| : |
| m_initialized(false) |
| { |
| if ( rhs.is_initialized() ) |
| construct( boost::move(rhs.get_impl()) ); |
| } |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| |
| template<class Expr, class PtrExpr> |
| explicit optional_base ( Expr&& expr, PtrExpr const* tag ) |
| : |
| m_initialized(false) |
| { |
| construct(boost::forward<Expr>(expr),tag); |
| } |
| |
| #else |
| // This is used for both converting and in-place constructions. |
| // Derived classes use the 'tag' to select the appropriate |
| // implementation (the correct 'construct()' overload) |
| template<class Expr> |
| explicit optional_base ( Expr const& expr, Expr const* tag ) |
| : |
| m_initialized(false) |
| { |
| construct(expr,tag); |
| } |
| |
| #endif |
| |
| optional_base& operator= ( optional_base const& rhs ) |
| { |
| this->assign(rhs); |
| return *this; |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| optional_base& operator= ( optional_base && rhs ) |
| BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value) |
| { |
| this->assign(static_cast<optional_base&&>(rhs)); |
| return *this; |
| } |
| #endif |
| |
| // No-throw (assuming T::~T() doesn't) |
| ~optional_base() { destroy() ; } |
| |
| // Assigns from another optional<T> (deep-copies the rhs value) |
| void assign ( optional_base const& rhs ) |
| { |
| if (is_initialized()) |
| { |
| if ( rhs.is_initialized() ) |
| assign_value(rhs.get_impl()); |
| else destroy(); |
| } |
| else |
| { |
| if ( rhs.is_initialized() ) |
| construct(rhs.get_impl()); |
| } |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Assigns from another optional<T> (deep-moves the rhs value) |
| void assign ( optional_base&& rhs ) |
| { |
| if (is_initialized()) |
| { |
| if ( rhs.is_initialized() ) |
| assign_value( boost::move(rhs.get_impl()) ); |
| else destroy(); |
| } |
| else |
| { |
| if ( rhs.is_initialized() ) |
| construct(boost::move(rhs.get_impl())); |
| } |
| } |
| #endif |
| |
| // Assigns from another _convertible_ optional<U> (deep-copies the rhs value) |
| template<class U> |
| void assign ( optional<U> const& rhs ) |
| { |
| if (is_initialized()) |
| { |
| if ( rhs.is_initialized() ) |
| #ifndef BOOST_OPTIONAL_CONFIG_RESTORE_ASSIGNMENT_OF_NONCONVERTIBLE_TYPES |
| assign_value( rhs.get() ); |
| #else |
| assign_value( static_cast<value_type>(rhs.get()) ); |
| #endif |
| |
| else destroy(); |
| } |
| else |
| { |
| if ( rhs.is_initialized() ) |
| #ifndef BOOST_OPTIONAL_CONFIG_RESTORE_ASSIGNMENT_OF_NONCONVERTIBLE_TYPES |
| construct(rhs.get()); |
| #else |
| construct(static_cast<value_type>(rhs.get())); |
| #endif |
| } |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // move-assigns from another _convertible_ optional<U> (deep-moves from the rhs value) |
| template<class U> |
| void assign ( optional<U>&& rhs ) |
| { |
| typedef BOOST_DEDUCED_TYPENAME optional<U>::rval_reference_type ref_type; |
| if (is_initialized()) |
| { |
| if ( rhs.is_initialized() ) |
| assign_value( static_cast<ref_type>(rhs.get()) ); |
| else destroy(); |
| } |
| else |
| { |
| if ( rhs.is_initialized() ) |
| construct(static_cast<ref_type>(rhs.get())); |
| } |
| } |
| #endif |
| |
| // Assigns from a T (deep-copies the rhs value) |
| void assign ( argument_type val ) |
| { |
| if (is_initialized()) |
| assign_value(val); |
| else construct(val); |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Assigns from a T (deep-moves the rhs value) |
| void assign ( rval_reference_type val ) |
| { |
| if (is_initialized()) |
| assign_value( boost::move(val) ); |
| else construct( boost::move(val) ); |
| } |
| #endif |
| |
| // Assigns from "none", destroying the current value, if any, leaving this UNINITIALIZED |
| // No-throw (assuming T::~T() doesn't) |
| void assign ( none_t ) BOOST_NOEXCEPT { destroy(); } |
| |
| #ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| template<class Expr, class ExprPtr> |
| void assign_expr ( Expr&& expr, ExprPtr const* tag ) |
| { |
| if (is_initialized()) |
| assign_expr_to_initialized(boost::forward<Expr>(expr),tag); |
| else construct(boost::forward<Expr>(expr),tag); |
| } |
| #else |
| template<class Expr> |
| void assign_expr ( Expr const& expr, Expr const* tag ) |
| { |
| if (is_initialized()) |
| assign_expr_to_initialized(expr,tag); |
| else construct(expr,tag); |
| } |
| #endif |
| |
| #endif |
| |
| public : |
| |
| // Destroys the current value, if any, leaving this UNINITIALIZED |
| // No-throw (assuming T::~T() doesn't) |
| void reset() BOOST_NOEXCEPT { destroy(); } |
| |
| // **DEPPRECATED** Replaces the current value -if any- with 'val' |
| void reset ( argument_type val ) { assign(val); } |
| |
| // Returns a pointer to the value if this is initialized, otherwise, |
| // returns NULL. |
| // No-throw |
| pointer_const_type get_ptr() const { return m_initialized ? get_ptr_impl() : 0 ; } |
| pointer_type get_ptr() { return m_initialized ? get_ptr_impl() : 0 ; } |
| |
| bool is_initialized() const BOOST_NOEXCEPT { return m_initialized ; } |
| |
| protected : |
| |
| void construct ( argument_type val ) |
| { |
| ::new (m_storage.address()) value_type(val) ; |
| m_initialized = true ; |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| void construct ( rval_reference_type val ) |
| { |
| ::new (m_storage.address()) value_type( boost::move(val) ) ; |
| m_initialized = true ; |
| } |
| #endif |
| |
| |
| #if (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES) |
| // Constructs in-place |
| // upon exception *this is always uninitialized |
| template<class... Args> |
| void construct ( in_place_init_t, Args&&... args ) |
| { |
| ::new (m_storage.address()) value_type( boost::forward<Args>(args)... ) ; |
| m_initialized = true ; |
| } |
| |
| template<class... Args> |
| void emplace_assign ( Args&&... args ) |
| { |
| destroy(); |
| construct(in_place_init, boost::forward<Args>(args)...); |
| } |
| |
| template<class... Args> |
| explicit optional_base ( in_place_init_t, Args&&... args ) |
| : |
| m_initialized(false) |
| { |
| construct(in_place_init, boost::forward<Args>(args)...); |
| } |
| |
| template<class... Args> |
| explicit optional_base ( in_place_init_if_t, bool cond, Args&&... args ) |
| : |
| m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init, boost::forward<Args>(args)...); |
| } |
| #elif (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) |
| template<class Arg> |
| void construct ( in_place_init_t, Arg&& arg ) |
| { |
| ::new (m_storage.address()) value_type( boost::forward<Arg>(arg) ); |
| m_initialized = true ; |
| } |
| |
| void construct ( in_place_init_t ) |
| { |
| ::new (m_storage.address()) value_type(); |
| m_initialized = true ; |
| } |
| |
| template<class Arg> |
| void emplace_assign ( Arg&& arg ) |
| { |
| destroy(); |
| construct(in_place_init, boost::forward<Arg>(arg)) ; |
| } |
| |
| void emplace_assign () |
| { |
| destroy(); |
| construct(in_place_init) ; |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_t, Arg&& arg ) |
| : |
| m_initialized(false) |
| { |
| construct(in_place_init, boost::forward<Arg>(arg)); |
| } |
| |
| explicit optional_base ( in_place_init_t ) |
| : |
| m_initialized(false) |
| { |
| construct(in_place_init); |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_if_t, bool cond, Arg&& arg ) |
| : |
| m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init, boost::forward<Arg>(arg)); |
| } |
| |
| explicit optional_base ( in_place_init_if_t, bool cond ) |
| : |
| m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init); |
| } |
| |
| #else |
| |
| template<class Arg> |
| void construct ( in_place_init_t, const Arg& arg ) |
| { |
| ::new (m_storage.address()) value_type( arg ); |
| m_initialized = true ; |
| } |
| |
| template<class Arg> |
| void construct ( in_place_init_t, Arg& arg ) |
| { |
| ::new (m_storage.address()) value_type( arg ); |
| m_initialized = true ; |
| } |
| |
| void construct ( in_place_init_t ) |
| { |
| ::new (m_storage.address()) value_type(); |
| m_initialized = true ; |
| } |
| |
| template<class Arg> |
| void emplace_assign ( const Arg& arg ) |
| { |
| destroy(); |
| construct(in_place_init, arg); |
| } |
| |
| template<class Arg> |
| void emplace_assign ( Arg& arg ) |
| { |
| destroy(); |
| construct(in_place_init, arg); |
| } |
| |
| void emplace_assign () |
| { |
| destroy(); |
| construct(in_place_init); |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_t, const Arg& arg ) |
| : m_initialized(false) |
| { |
| construct(in_place_init, arg); |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_t, Arg& arg ) |
| : m_initialized(false) |
| { |
| construct(in_place_init, arg); |
| } |
| |
| explicit optional_base ( in_place_init_t ) |
| : m_initialized(false) |
| { |
| construct(in_place_init); |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_if_t, bool cond, const Arg& arg ) |
| : m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init, arg); |
| } |
| |
| template<class Arg> |
| explicit optional_base ( in_place_init_if_t, bool cond, Arg& arg ) |
| : m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init, arg); |
| } |
| |
| explicit optional_base ( in_place_init_if_t, bool cond ) |
| : m_initialized(false) |
| { |
| if ( cond ) |
| construct(in_place_init); |
| } |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Constructs in-place using the given factory |
| template<class Expr> |
| void construct ( Expr&& factory, in_place_factory_base const* ) |
| { |
| boost_optional_detail::construct<value_type>(factory, m_storage.address()); |
| m_initialized = true ; |
| } |
| |
| // Constructs in-place using the given typed factory |
| template<class Expr> |
| void construct ( Expr&& factory, typed_in_place_factory_base const* ) |
| { |
| factory.apply(m_storage.address()) ; |
| m_initialized = true ; |
| } |
| |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr&& factory, in_place_factory_base const* tag ) |
| { |
| destroy(); |
| construct(factory,tag); |
| } |
| |
| // Constructs in-place using the given typed factory |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr&& factory, typed_in_place_factory_base const* tag ) |
| { |
| destroy(); |
| construct(factory,tag); |
| } |
| |
| #else |
| // Constructs in-place using the given factory |
| template<class Expr> |
| void construct ( Expr const& factory, in_place_factory_base const* ) |
| { |
| boost_optional_detail::construct<value_type>(factory, m_storage.address()); |
| m_initialized = true ; |
| } |
| |
| // Constructs in-place using the given typed factory |
| template<class Expr> |
| void construct ( Expr const& factory, typed_in_place_factory_base const* ) |
| { |
| factory.apply(m_storage.address()) ; |
| m_initialized = true ; |
| } |
| |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr const& factory, in_place_factory_base const* tag ) |
| { |
| destroy(); |
| construct(factory,tag); |
| } |
| |
| // Constructs in-place using the given typed factory |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr const& factory, typed_in_place_factory_base const* tag ) |
| { |
| destroy(); |
| construct(factory,tag); |
| } |
| #endif |
| |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Constructs using any expression implicitly convertible to the single argument |
| // of a one-argument T constructor. |
| // Converting constructions of optional<T> from optional<U> uses this function with |
| // 'Expr' being of type 'U' and relying on a converting constructor of T from U. |
| template<class Expr> |
| void construct ( Expr&& expr, void const* ) |
| { |
| new (m_storage.address()) value_type(boost::forward<Expr>(expr)) ; |
| m_initialized = true ; |
| } |
| |
| // Assigns using a form any expression implicitly convertible to the single argument |
| // of a T's assignment operator. |
| // Converting assignments of optional<T> from optional<U> uses this function with |
| // 'Expr' being of type 'U' and relying on a converting assignment of T from U. |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr&& expr, void const* ) |
| { |
| assign_value( boost::forward<Expr>(expr) ); |
| } |
| #else |
| // Constructs using any expression implicitly convertible to the single argument |
| // of a one-argument T constructor. |
| // Converting constructions of optional<T> from optional<U> uses this function with |
| // 'Expr' being of type 'U' and relying on a converting constructor of T from U. |
| template<class Expr> |
| void construct ( Expr const& expr, void const* ) |
| { |
| new (m_storage.address()) value_type(expr) ; |
| m_initialized = true ; |
| } |
| |
| // Assigns using a form any expression implicitly convertible to the single argument |
| // of a T's assignment operator. |
| // Converting assignments of optional<T> from optional<U> uses this function with |
| // 'Expr' being of type 'U' and relying on a converting assignment of T from U. |
| template<class Expr> |
| void assign_expr_to_initialized ( Expr const& expr, void const* ) |
| { |
| assign_value(expr); |
| } |
| |
| #endif |
| |
| #ifdef BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION |
| // BCB5.64 (and probably lower versions) workaround. |
| // The in-place factories are supported by means of catch-all constructors |
| // and assignment operators (the functions are parameterized in terms of |
| // an arbitrary 'Expr' type) |
| // This compiler incorrectly resolves the overload set and sinks optional<T> and optional<U> |
| // to the 'Expr'-taking functions even though explicit overloads are present for them. |
| // Thus, the following overload is needed to properly handle the case when the 'lhs' |
| // is another optional. |
| // |
| // For VC<=70 compilers this workaround dosen't work becasue the comnpiler issues and error |
| // instead of choosing the wrong overload |
| // |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Notice that 'Expr' will be optional<T> or optional<U> (but not optional_base<..>) |
| template<class Expr> |
| void construct ( Expr&& expr, optional_tag const* ) |
| { |
| if ( expr.is_initialized() ) |
| { |
| // An exception can be thrown here. |
| // It it happens, THIS will be left uninitialized. |
| new (m_storage.address()) value_type(boost::move(expr.get())) ; |
| m_initialized = true ; |
| } |
| } |
| #else |
| // Notice that 'Expr' will be optional<T> or optional<U> (but not optional_base<..>) |
| template<class Expr> |
| void construct ( Expr const& expr, optional_tag const* ) |
| { |
| if ( expr.is_initialized() ) |
| { |
| // An exception can be thrown here. |
| // It it happens, THIS will be left uninitialized. |
| new (m_storage.address()) value_type(expr.get()) ; |
| m_initialized = true ; |
| } |
| } |
| #endif |
| #endif // defined BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION |
| |
| void assign_value ( argument_type val ) { get_impl() = val; } |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| void assign_value ( rval_reference_type val ) { get_impl() = static_cast<rval_reference_type>(val); } |
| #endif |
| |
| void destroy() |
| { |
| if ( m_initialized ) |
| destroy_impl() ; |
| } |
| |
| reference_const_type get_impl() const { return m_storage.ref() ; } |
| reference_type get_impl() { return m_storage.ref() ; } |
| |
| pointer_const_type get_ptr_impl() const { return m_storage.ptr_ref(); } |
| pointer_type get_ptr_impl() { return m_storage.ptr_ref(); } |
| |
| private : |
| |
| #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1900)) |
| void destroy_impl ( ) { m_storage.ptr_ref()->~T() ; m_initialized = false ; } |
| #else |
| void destroy_impl ( ) { m_storage.ref().T::~T() ; m_initialized = false ; } |
| #endif |
| |
| bool m_initialized ; |
| storage_type m_storage ; |
| } ; |
| |
| #include <boost/optional/detail/optional_trivially_copyable_base.hpp> |
| |
| // definition of metafunction is_optional_val_init_candidate |
| template <typename U> |
| struct is_optional_related |
| : 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 |
| || boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<U>::type, in_place_init_if_t>::value, |
| boost::true_type, boost::false_type>::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 |
| {}; |
| |
| template <typename T, typename U> |
| struct is_optional_constructible : boost::is_constructible<T, U> |
| {}; |
| |
| #else |
| |
| template <typename, typename> |
| struct is_convertible_to_T_or_factory : boost::true_type |
| {}; |
| |
| template <typename T, typename U> |
| struct is_optional_constructible : boost::true_type |
| {}; |
| |
| #endif // is_convertible condition |
| |
| template <typename T, typename U, bool = is_optional_related<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 |
| {}; |
| |
| } // namespace optional_detail |
| |
| namespace optional_config { |
| |
| template <typename T> |
| struct optional_uses_direct_storage_for |
| : boost::conditional<(boost::is_scalar<T>::value && !boost::is_const<T>::value && !boost::is_volatile<T>::value) |
| , boost::true_type, boost::false_type>::type |
| {}; |
| |
| } // namespace optional_config |
| |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_DIRECT_STORAGE_SPEC |
| # define BOOST_OPTIONAL_BASE_TYPE(T) boost::conditional< optional_config::optional_uses_direct_storage_for<T>::value, \ |
| optional_detail::tc_optional_base<T>, \ |
| optional_detail::optional_base<T> \ |
| >::type |
| #else |
| # define BOOST_OPTIONAL_BASE_TYPE(T) optional_detail::optional_base<T> |
| #endif |
| |
| template<class T> |
| class optional |
| : public BOOST_OPTIONAL_BASE_TYPE(T) |
| { |
| typedef typename BOOST_OPTIONAL_BASE_TYPE(T) base ; |
| |
| public : |
| |
| typedef optional<T> this_type ; |
| |
| typedef BOOST_DEDUCED_TYPENAME base::value_type value_type ; |
| typedef BOOST_DEDUCED_TYPENAME base::reference_type reference_type ; |
| typedef BOOST_DEDUCED_TYPENAME base::reference_const_type reference_const_type ; |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| typedef BOOST_DEDUCED_TYPENAME base::rval_reference_type rval_reference_type ; |
| typedef BOOST_DEDUCED_TYPENAME base::reference_type_of_temporary_wrapper reference_type_of_temporary_wrapper ; |
| #endif |
| typedef BOOST_DEDUCED_TYPENAME base::pointer_type pointer_type ; |
| typedef BOOST_DEDUCED_TYPENAME base::pointer_const_type pointer_const_type ; |
| typedef BOOST_DEDUCED_TYPENAME base::argument_type argument_type ; |
| |
| // Creates an optional<T> uninitialized. |
| // No-throw |
| optional() BOOST_NOEXCEPT : base() {} |
| |
| // Creates an optional<T> uninitialized. |
| // No-throw |
| optional( none_t none_ ) BOOST_NOEXCEPT : base(none_) {} |
| |
| // Creates an optional<T> initialized with 'val'. |
| // Can throw if T::T(T const&) does |
| optional ( argument_type val ) : base(optional_detail::init_value_tag(), val) {} |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Creates an optional<T> initialized with 'move(val)'. |
| // Can throw if T::T(T &&) does |
| optional ( rval_reference_type val ) : base(optional_detail::init_value_tag(), boost::forward<T>(val)) |
| {} |
| #endif |
| |
| // Creates an optional<T> initialized with 'val' IFF cond is true, otherwise creates an uninitialized optional. |
| // Can throw if T::T(T const&) does |
| optional ( bool cond, argument_type val ) : base(cond,val) {} |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| /// Creates an optional<T> initialized with 'val' IFF cond is true, otherwise creates an uninitialized optional. |
| // Can throw if T::T(T &&) does |
| optional ( bool cond, rval_reference_type val ) : base( cond, boost::forward<T>(val) ) |
| {} |
| #endif |
| |
| // NOTE: MSVC needs templated versions first |
| |
| // Creates a deep copy of another convertible optional<U> |
| // Requires a valid conversion from U to T. |
| // Can throw if T::T(U const&) does |
| template<class U> |
| explicit optional ( optional<U> const& rhs |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_SFINAE_FRIENDLY_CONSTRUCTORS |
| ,BOOST_DEDUCED_TYPENAME boost::enable_if< optional_detail::is_optional_constructible<T, U const&>, bool>::type = true |
| #endif |
| ) |
| : |
| base() |
| { |
| if ( rhs.is_initialized() ) |
| this->construct(rhs.get()); |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Creates a deep move of another convertible optional<U> |
| // Requires a valid conversion from U to T. |
| // Can throw if T::T(U&&) does |
| template<class U> |
| explicit optional ( optional<U> && rhs |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_SFINAE_FRIENDLY_CONSTRUCTORS |
| ,BOOST_DEDUCED_TYPENAME boost::enable_if< optional_detail::is_optional_constructible<T, U>, bool>::type = true |
| #endif |
| ) |
| : |
| base() |
| { |
| if ( rhs.is_initialized() ) |
| this->construct( boost::move(rhs.get()) ); |
| } |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT |
| // Creates an optional<T> with an expression which can be either |
| // (a) An instance of InPlaceFactory (i.e. in_place(a,b,...,n); |
| // (b) An instance of TypedInPlaceFactory ( i.e. in_place<T>(a,b,...,n); |
| // (c) Any expression implicitly convertible to the single type |
| // of a one-argument T's constructor. |
| // (d*) Weak compilers (BCB) might also resolved Expr as optional<T> and optional<U> |
| // even though explicit overloads are present for these. |
| // Depending on the above some T ctor is called. |
| // Can throw if the resolved T ctor throws. |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| |
| |
| template<class Expr> |
| explicit optional ( Expr&& expr, |
| BOOST_DEDUCED_TYPENAME boost::enable_if< optional_detail::is_optional_val_init_candidate<T, Expr>, bool>::type = true |
| ) |
| : base(boost::forward<Expr>(expr),boost::addressof(expr)) |
| {} |
| |
| #else |
| template<class Expr> |
| explicit optional ( Expr const& expr ) : base(expr,boost::addressof(expr)) {} |
| #endif // !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| #endif // !defined BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT |
| |
| // Creates a deep copy of another optional<T> |
| // Can throw if T::T(T const&) does |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_MOVE_FUNCTIONS |
| optional ( optional const& ) = default; |
| #else |
| optional ( optional const& rhs ) : base( static_cast<base const&>(rhs) ) {} |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Creates a deep move of another optional<T> |
| // Can throw if T::T(T&&) does |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_MOVE_FUNCTIONS |
| optional ( optional && ) = default; |
| #else |
| optional ( optional && rhs ) |
| BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value) |
| : base( boost::move(rhs) ) |
| {} |
| #endif |
| |
| #endif |
| |
| #if BOOST_WORKAROUND(_MSC_VER, <= 1600) |
| // On old MSVC compilers the implicitly declared dtor is not called |
| ~optional() {} |
| #endif |
| |
| |
| #if !defined(BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT) && !defined(BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION) |
| // Assigns from an expression. See corresponding constructor. |
| // Basic Guarantee: If the resolved T ctor throws, this is left UNINITIALIZED |
| #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 |
| operator= ( Expr&& expr ) |
| { |
| this->assign_expr(boost::forward<Expr>(expr),boost::addressof(expr)); |
| return *this ; |
| } |
| |
| #else |
| template<class Expr> |
| optional& operator= ( Expr const& expr ) |
| { |
| this->assign_expr(expr,boost::addressof(expr)); |
| return *this ; |
| } |
| #endif // !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| #endif // !defined(BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT) && !defined(BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION) |
| |
| // Copy-assigns from another convertible optional<U> (converts && deep-copies the rhs value) |
| // Requires a valid conversion from U to T. |
| // Basic Guarantee: If T::T( U const& ) throws, this is left UNINITIALIZED |
| template<class U> |
| optional& operator= ( optional<U> const& rhs ) |
| { |
| this->assign(rhs); |
| return *this ; |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Move-assigns from another convertible optional<U> (converts && deep-moves the rhs value) |
| // Requires a valid conversion from U to T. |
| // Basic Guarantee: If T::T( U && ) throws, this is left UNINITIALIZED |
| template<class U> |
| optional& operator= ( optional<U> && rhs ) |
| { |
| this->assign(boost::move(rhs)); |
| return *this ; |
| } |
| #endif |
| |
| // Assigns from another optional<T> (deep-copies the rhs value) |
| // Basic Guarantee: If T::T( T const& ) throws, this is left UNINITIALIZED |
| // (NOTE: On BCB, this operator is not actually called and left is left UNMODIFIED in case of a throw) |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_MOVE_FUNCTIONS |
| optional& operator= ( optional const& rhs ) = default; |
| #else |
| optional& operator= ( optional const& rhs ) |
| { |
| this->assign( static_cast<base const&>(rhs) ) ; |
| return *this ; |
| } |
| #endif |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Assigns from another optional<T> (deep-moves the rhs value) |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_MOVE_FUNCTIONS |
| optional& operator= ( optional && ) = default; |
| #else |
| optional& operator= ( optional && rhs ) |
| BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value) |
| { |
| this->assign( static_cast<base &&>(rhs) ) ; |
| return *this ; |
| } |
| #endif |
| |
| #endif // BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| |
| #ifndef BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX |
| |
| // Assigns from a T (deep-moves/copies the rhs value) |
| template <typename T_> |
| BOOST_DEDUCED_TYPENAME boost::enable_if<boost::is_same<T, BOOST_DEDUCED_TYPENAME boost::decay<T_>::type>, optional&>::type |
| operator= ( T_&& val ) |
| { |
| this->assign( boost::forward<T_>(val) ) ; |
| return *this ; |
| } |
| |
| #else |
| |
| // Assigns from a T (deep-copies the rhs value) |
| // Basic Guarantee: If T::( T const& ) throws, this is left UNINITIALIZED |
| optional& operator= ( argument_type val ) |
| { |
| this->assign( val ) ; |
| return *this ; |
| } |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| // Assigns from a T (deep-moves the rhs value) |
| optional& operator= ( rval_reference_type val ) |
| { |
| this->assign( boost::move(val) ) ; |
| return *this ; |
| } |
| #endif |
| |
| #endif // BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX |
| |
| // Assigns from a "none" |
| // Which destroys the current value, if any, leaving this UNINITIALIZED |
| // No-throw (assuming T::~T() doesn't) |
| optional& operator= ( none_t none_ ) BOOST_NOEXCEPT |
| { |
| this->assign( none_ ) ; |
| return *this ; |
| } |
| |
| #if (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES) |
| // Constructs in-place |
| // upon exception *this is always uninitialized |
| template<class... Args> |
| void emplace ( Args&&... args ) |
| { |
| this->emplace_assign( boost::forward<Args>(args)... ); |
| } |
| |
| template<class... Args> |
| explicit optional ( in_place_init_t, Args&&... args ) |
| : base( in_place_init, boost::forward<Args>(args)... ) |
| {} |
| |
| template<class... Args> |
| explicit optional ( in_place_init_if_t, bool cond, Args&&... args ) |
| : base( in_place_init_if, cond, boost::forward<Args>(args)... ) |
| {} |
| |
| #elif (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) |
| template<class Arg> |
| void emplace ( Arg&& arg ) |
| { |
| this->emplace_assign( boost::forward<Arg>(arg) ); |
| } |
| |
| void emplace () |
| { |
| this->emplace_assign(); |
| } |
| |
| template<class Args> |
| explicit optional ( in_place_init_t, Args&& args ) |
| : base( in_place_init, boost::forward<Args>(args) ) |
| {} |
| |
| explicit optional ( in_place_init_t ) |
| : base( in_place_init ) |
| {} |
| |
| template<class Args> |
| explicit optional ( in_place_init_if_t, bool cond, Args&& args ) |
| : base( in_place_init_if, cond, boost::forward<Args>(args) ) |
| {} |
| |
| explicit optional ( in_place_init_if_t, bool cond ) |
| : base( in_place_init_if, cond ) |
| {} |
| #else |
| template<class Arg> |
| void emplace ( const Arg& arg ) |
| { |
| this->emplace_assign( arg ); |
| } |
| |
| template<class Arg> |
| void emplace ( Arg& arg ) |
| { |
| this->emplace_assign( arg ); |
| } |
| |
| void emplace () |
| { |
| this->emplace_assign(); |
| } |
| |
| template<class Arg> |
| explicit optional ( in_place_init_t, const Arg& arg ) |
| : base( in_place_init, arg ) |
| {} |
| |
| template<class Arg> |
| explicit optional ( in_place_init_t, Arg& arg ) |
| : base( in_place_init, arg ) |
| {} |
| |
| explicit optional ( in_place_init_t ) |
| : base( in_place_init ) |
| {} |
| |
| template<class Arg> |
| explicit optional ( in_place_init_if_t, bool cond, const Arg& arg ) |
| : base( in_place_init_if, cond, arg ) |
| {} |
| |
| template<class Arg> |
| explicit optional ( in_place_init_if_t, bool cond, Arg& arg ) |
| : base( in_place_init_if, cond, arg ) |
| {} |
| |
| explicit optional ( in_place_init_if_t, bool cond ) |
| : base( in_place_init_if, cond ) |
| {} |
| #endif |
| |
| void swap( optional & arg ) |
| BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value) |
| { |
| // allow for Koenig lookup |
| boost::swap(*this, arg); |
| } |
| |
| |
| // Returns a reference to the value if this is initialized, otherwise, |
| // the behaviour is UNDEFINED |
| // No-throw |
| reference_const_type get() const { BOOST_ASSERT(this->is_initialized()) ; return this->get_impl(); } |
| reference_type get() { BOOST_ASSERT(this->is_initialized()) ; return this->get_impl(); } |
| |
| // Returns a copy of the value if this is initialized, 'v' otherwise |
| reference_const_type get_value_or ( reference_const_type v ) const { return this->is_initialized() ? get() : v ; } |
| reference_type get_value_or ( reference_type v ) { return this->is_initialized() ? get() : v ; } |
| |
| // Returns a pointer to the value if this is initialized, otherwise, |
| // the behaviour is UNDEFINED |
| // No-throw |
| pointer_const_type operator->() const { BOOST_ASSERT(this->is_initialized()) ; return this->get_ptr_impl() ; } |
| pointer_type operator->() { BOOST_ASSERT(this->is_initialized()) ; return this->get_ptr_impl() ; } |
| |
| // Returns a reference to the value if this is initialized, otherwise, |
| // the behaviour is UNDEFINED |
| // No-throw |
| #if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) |
| reference_const_type operator *() const& { return this->get() ; } |
| reference_type operator *() & { return this->get() ; } |
| reference_type_of_temporary_wrapper operator *() && { return boost::move(this->get()) ; } |
| #else |
| reference_const_type operator *() const { return this->get() ; } |
| reference_type operator *() { return this->get() ; } |
| #endif // !defined BOOST_NO_CXX11_REF_QUALIFIERS |
| |
| #if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) |
| reference_const_type value() const& |
| { |
| if (this->is_initialized()) |
| return this->get() ; |
| else |
| throw_exception(bad_optional_access()); |
| } |
| |
| reference_type value() & |
| { |
| if (this->is_initialized()) |
| return this->get() ; |
| else |
| throw_exception(bad_optional_access()); |
| } |
| |
| reference_type_of_temporary_wrapper value() && |
| { |
| if (this->is_initialized()) |
| return boost::move(this->get()) ; |
| else |
| throw_exception(bad_optional_access()); |
| } |
| |
| #else |
| reference_const_type value() const |
| { |
| if (this->is_initialized()) |
| return this->get() ; |
| else |
| throw_exception(bad_optional_access()); |
| } |
| |
| reference_type value() |
| { |
| if (this->is_initialized()) |
| return this->get() ; |
| else |
| throw_exception(bad_optional_access()); |
| } |
| #endif |
| |
| |
| #ifndef BOOST_NO_CXX11_REF_QUALIFIERS |
| template <class U> |
| value_type value_or ( U&& v ) const& |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return boost::forward<U>(v); |
| } |
| |
| template <class U> |
| value_type value_or ( U&& v ) && |
| { |
| if (this->is_initialized()) |
| return boost::move(get()); |
| else |
| return boost::forward<U>(v); |
| } |
| #elif !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| template <class U> |
| value_type value_or ( U&& v ) const |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return boost::forward<U>(v); |
| } |
| #else |
| template <class U> |
| value_type value_or ( U const& v ) const |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return v; |
| } |
| |
| template <class U> |
| value_type value_or ( U& v ) const |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return v; |
| } |
| #endif |
| |
| |
| #if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) |
| template <typename F> |
| value_type value_or_eval ( F f ) const& |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return f(); |
| } |
| |
| template <typename F> |
| value_type value_or_eval ( F f ) && |
| { |
| if (this->is_initialized()) |
| return boost::move(get()); |
| else |
| return f(); |
| } |
| |
| template <typename F> |
| optional<typename boost::result_of<F(reference_type)>::type> map(F f) & |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename boost::result_of<F(reference_const_type)>::type> map(F f) const& |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename boost::result_of<F(reference_type_of_temporary_wrapper)>::type> map(F f) && |
| { |
| if (this->has_value()) |
| return f(boost::move(this->get())); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename optional_detail::optional_value_type<typename boost::result_of<F(reference_type)>::type>::type> flat_map(F f) & |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename optional_detail::optional_value_type<typename boost::result_of<F(reference_const_type)>::type>::type> flat_map(F f) const& |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename optional_detail::optional_value_type<typename boost::result_of<F(reference_type_of_temporary_wrapper)>::type>::type> flat_map(F f) && |
| { |
| if (this->has_value()) |
| return f(boost::move(get())); |
| else |
| return none; |
| } |
| |
| #else |
| template <typename F> |
| value_type value_or_eval ( F f ) const |
| { |
| if (this->is_initialized()) |
| return get(); |
| else |
| return f(); |
| } |
| |
| template <typename F> |
| optional<typename boost::result_of<F(reference_type)>::type> map(F f) |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename boost::result_of<F(reference_const_type)>::type> map(F f) const |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename optional_detail::optional_value_type<typename boost::result_of<F(reference_type)>::type>::type> flat_map(F f) |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| template <typename F> |
| optional<typename optional_detail::optional_value_type<typename boost::result_of<F(reference_const_type)>::type>::type> flat_map(F f) const |
| { |
| if (this->has_value()) |
| return f(get()); |
| else |
| return none; |
| } |
| |
| #endif |
| |
| bool has_value() const BOOST_NOEXCEPT { return this->is_initialized() ; } |
| |
| bool operator!() const BOOST_NOEXCEPT { return !this->is_initialized() ; } |
| |
| BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT() |
| } ; |
| |
| } // namespace boost |
| |
| #endif // BOOST_OPTIONAL_CONFIG_USE_OLD_IMPLEMENTATION_OF_OPTIONAL |
| |
| namespace boost { |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| template<class T> |
| class optional<T&&> |
| { |
| BOOST_STATIC_ASSERT_MSG(sizeof(T) == 0, "Optional rvalue references are illegal."); |
| } ; |
| #endif |
| |
| } // namespace boost |
| |
| #ifndef BOOST_OPTIONAL_CONFIG_DONT_SPECIALIZE_OPTIONAL_REFS |
| # include <boost/optional/detail/optional_reference_spec.hpp> |
| #endif |
| |
| namespace boost { |
| |
| #ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| |
| template<class T> |
| inline |
| optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type> make_optional ( T && v ) |
| { |
| return optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type>(boost::forward<T>(v)); |
| } |
| |
| // Returns optional<T>(cond,v) |
| template<class T> |
| inline |
| optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type> make_optional ( bool cond, T && v ) |
| { |
| return optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type>(cond,boost::forward<T>(v)); |
| } |
| |
| #else |
| |
| // Returns optional<T>(v) |
| template<class T> |
| inline |
| optional<T> make_optional ( T const& v ) |
| { |
| return optional<T>(v); |
| } |
| |
| // Returns optional<T>(cond,v) |
| template<class T> |
| inline |
| optional<T> make_optional ( bool cond, T const& v ) |
| { |
| return optional<T>(cond,v); |
| } |
| |
| #endif // BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES |
| |
| // Returns a reference to the value if this is initialized, otherwise, the behaviour is UNDEFINED. |
| // No-throw |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::reference_const_type |
| get ( optional<T> const& opt ) |
| { |
| return opt.get() ; |
| } |
| |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::reference_type |
| get ( optional<T>& opt ) |
| { |
| return opt.get() ; |
| } |
| |
| // Returns a pointer to the value if this is initialized, otherwise, returns NULL. |
| // No-throw |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::pointer_const_type |
| get ( optional<T> const* opt ) |
| { |
| return opt->get_ptr() ; |
| } |
| |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::pointer_type |
| get ( optional<T>* opt ) |
| { |
| return opt->get_ptr() ; |
| } |
| |
| // Returns a reference to the value if this is initialized, otherwise, the behaviour is UNDEFINED. |
| // No-throw |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::reference_const_type |
| get_optional_value_or ( optional<T> const& opt, BOOST_DEDUCED_TYPENAME optional<T>::reference_const_type v ) |
| { |
| return opt.get_value_or(v) ; |
| } |
| |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::reference_type |
| get_optional_value_or ( optional<T>& opt, BOOST_DEDUCED_TYPENAME optional<T>::reference_type v ) |
| { |
| return opt.get_value_or(v) ; |
| } |
| |
| // Returns a pointer to the value if this is initialized, otherwise, returns NULL. |
| // No-throw |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::pointer_const_type |
| get_pointer ( optional<T> const& opt ) |
| { |
| return opt.get_ptr() ; |
| } |
| |
| template<class T> |
| inline |
| BOOST_DEDUCED_TYPENAME optional<T>::pointer_type |
| get_pointer ( optional<T>& opt ) |
| { |
| return opt.get_ptr() ; |
| } |
| |
| } // namespace boost |
| |
| namespace boost { |
| |
| // The following declaration prevents a bug where operator safe-bool is used upon streaming optional object if you forget the IO header. |
| template<class CharType, class CharTrait> |
| std::basic_ostream<CharType, CharTrait>& |
| operator<<(std::basic_ostream<CharType, CharTrait>& os, optional_detail::optional_tag const&) |
| { |
| BOOST_STATIC_ASSERT_MSG(sizeof(CharType) == 0, "If you want to output boost::optional, include header <boost/optional/optional_io.hpp>"); |
| return os; |
| } |
| |
| } // namespace boost |
| |
| #include <boost/optional/detail/optional_relops.hpp> |
| #include <boost/optional/detail/optional_swap.hpp> |
| |
| #endif // header guard |