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-rw-r--r--3rd_party/include/opentracing/expected/LICENSE23
-rw-r--r--3rd_party/include/opentracing/expected/expected.hpp1245
2 files changed, 1268 insertions, 0 deletions
diff --git a/3rd_party/include/opentracing/expected/LICENSE b/3rd_party/include/opentracing/expected/LICENSE
new file mode 100644
index 0000000..7e4dcd5
--- /dev/null
+++ b/3rd_party/include/opentracing/expected/LICENSE
@@ -0,0 +1,23 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Martin Moene
+Copyright (c) 2015 Microsoft Corporation. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
diff --git a/3rd_party/include/opentracing/expected/expected.hpp b/3rd_party/include/opentracing/expected/expected.hpp
new file mode 100644
index 0000000..8283a77
--- /dev/null
+++ b/3rd_party/include/opentracing/expected/expected.hpp
@@ -0,0 +1,1245 @@
+// Copyright (C) 2016 Martin Moene.
+//
+// This version targets C++11 and later.
+//
+// This code is licensed under the MIT License (MIT).
+//
+// expected lite is based on:
+// A proposal to add a utility class to represent expected monad - Revision 2
+// by Vicente J. Botet Escriba and Pierre Talbot.
+
+#ifndef OPENTRACING_EXPECTED_LITE_HPP
+#define OPENTRACING_EXPECTED_LITE_HPP
+
+#include <cassert>
+#include <exception>
+#include <functional>
+#include <initializer_list>
+#include <new>
+#include <stdexcept>
+#include <type_traits>
+#include <utility>
+#include <opentracing/version.h>
+
+#define expected_lite_VERSION "0.0.0"
+
+// Compiler detection:
+
+#define nsel_CPP11_OR_GREATER ( __cplusplus >= 201103L )
+#define nsel_CPP14_OR_GREATER ( __cplusplus >= 201402L )
+
+#if nsel_CPP14_OR_GREATER
+# define nsel_constexpr14 constexpr
+#else
+# define nsel_constexpr14 /*constexpr*/
+#endif
+
+// Method enabling
+
+#define nsel_REQUIRES(...) \
+ typename std::enable_if<__VA_ARGS__, void*>::type = 0
+
+#define nsel_REQUIRES_0(...) \
+ template< bool B = (__VA_ARGS__), typename std::enable_if<B, int>::type = 0 >
+
+#define nsel_REQUIRES_T(...) \
+ typename = typename std::enable_if< (__VA_ARGS__), opentracing::expected_detail::enabler >::type
+
+namespace opentracing {
+BEGIN_OPENTRACING_ABI_NAMESPACE
+
+template< typename T, typename E >
+class expected;
+
+namespace expected_detail {
+
+/// for nsel_REQUIRES_T
+
+enum class enabler{};
+
+/// discriminated union to hold value or 'error'.
+
+template< typename T, typename E >
+union storage_t
+{
+ friend class expected<T,E>;
+
+private:
+ typedef T value_type;
+ typedef E error_type;
+
+ // no-op construction
+ storage_t() {}
+ ~storage_t() {}
+
+ void construct_value( value_type const & v )
+ {
+ new( &m_value ) value_type( v );
+ }
+
+ void construct_value( value_type && v )
+ {
+ new( &m_value ) value_type( std::forward<T>( v ) );
+ }
+
+ void destruct_value()
+ {
+ m_value.~value_type();
+ }
+
+ void construct_error( error_type const & e )
+ {
+ new( &m_error ) error_type( e );
+ }
+
+ void construct_error( error_type && e )
+ {
+ new( &m_error ) error_type( std::move( e ) );
+ }
+
+ void destruct_error()
+ {
+ m_error.~error_type();
+ }
+
+ constexpr value_type const & value() const &
+ {
+ return m_value;
+ }
+
+ value_type & value() &
+ {
+ return m_value;
+ }
+
+ constexpr value_type && value() const &&
+ {
+ return std::move( m_value );
+ }
+
+ const value_type * value_ptr() const
+ {
+ return &m_value;
+ }
+
+ value_type * value_ptr()
+ {
+ return &m_value;
+ }
+
+ error_type const & error() const
+ {
+ return m_error;
+ }
+
+ error_type & error()
+ {
+ return m_error;
+ }
+
+private:
+ value_type m_value;
+ error_type m_error;
+};
+
+/// discriminated union to hold only 'error'.
+
+template< typename E >
+union storage_t<void, E>
+{
+ friend class expected<void,E>;
+
+private:
+ typedef void value_type;
+ typedef E error_type;
+
+ // no-op construction
+ storage_t() {}
+ ~storage_t() {}
+
+ void construct_error( error_type const & e )
+ {
+ new( &m_error ) error_type( e );
+ }
+
+ void construct_error( error_type && e )
+ {
+ new( &m_error ) error_type( std::move( e ) );
+ }
+
+ void destruct_error()
+ {
+ m_error.~error_type();
+ }
+
+ error_type const & error() const
+ {
+ return m_error;
+ }
+
+ error_type & error()
+ {
+ return m_error;
+ }
+
+private:
+ error_type m_error;
+};
+
+} // namespace expected_detail
+
+/// class unexpected_type
+
+template< typename E = std::error_code >
+class unexpected_type
+{
+public:
+ typedef E error_type;
+
+ unexpected_type() = delete;
+
+ nsel_REQUIRES_0(
+ std::is_copy_constructible<error_type>::value )
+
+ constexpr explicit unexpected_type( error_type const & error )
+ : m_error( error )
+ {}
+
+ nsel_REQUIRES_0(
+ std::is_move_constructible<error_type>::value )
+
+ constexpr explicit unexpected_type( error_type && error )
+ : m_error( std::move( error ) )
+ {}
+
+ constexpr error_type const & value() const
+ {
+ return m_error;
+ }
+
+ error_type & value()
+ {
+ return m_error;
+ }
+
+private:
+ error_type m_error;
+};
+
+/// class unexpected_type, std::exception_ptr specialization
+
+template<>
+class unexpected_type< std::exception_ptr >
+{
+public:
+ typedef std::exception_ptr error_type;
+
+ unexpected_type() = delete;
+
+ ~unexpected_type(){}
+
+ explicit unexpected_type( std::exception_ptr const & error )
+ : m_error( error )
+ {}
+
+ explicit unexpected_type(std::exception_ptr && error )
+ : m_error( std::move( error ) )
+ {}
+
+ template< typename E >
+ explicit unexpected_type( E error )
+ : m_error( std::make_exception_ptr( error ) )
+ {}
+
+ std::exception_ptr const & value() const
+ {
+ return m_error;
+ }
+
+ std::exception_ptr & value()
+ {
+ return m_error;
+ }
+
+private:
+ std::exception_ptr m_error;
+};
+
+// unexpected: relational operators
+
+template< typename E >
+constexpr bool operator==( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return x.value() == y.value();
+}
+
+template< typename E >
+constexpr bool operator!=( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return ! ( x == y );
+}
+
+template< typename E >
+constexpr bool operator<( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return x.value() < y.value();
+}
+
+template< typename E >
+constexpr bool operator>( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return ( y < x );
+}
+
+template< typename E >
+constexpr bool operator<=( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return ! ( y < x );
+}
+
+template< typename E >
+constexpr bool operator>=( unexpected_type<E> const & x, unexpected_type<E> const & y )
+{
+ return ! ( x < y );
+}
+
+inline constexpr bool operator<( unexpected_type<std::exception_ptr> const & /*x*/, unexpected_type<std::exception_ptr> const & /*y*/ )
+{
+ return false;
+}
+
+inline constexpr bool operator>( unexpected_type<std::exception_ptr> const & /*x*/, unexpected_type<std::exception_ptr> const & /*y*/ )
+{
+ return false;
+}
+
+inline constexpr bool operator<=( unexpected_type<std::exception_ptr> const & x, unexpected_type<std::exception_ptr> const & y )
+{
+ return ( x == y );
+}
+
+inline constexpr bool operator>=( unexpected_type<std::exception_ptr> const & x, unexpected_type<std::exception_ptr> const & y )
+{
+ return ( x == y );
+}
+
+// unexpected: traits
+
+template <typename E>
+struct is_unexpected : std::false_type {};
+
+template <typename E>
+struct is_unexpected< unexpected_type<E> > : std::true_type {};
+
+// unexpected: factory
+
+template< typename E>
+nsel_constexpr14 auto
+make_unexpected( E && v) -> unexpected_type< typename std::decay<E>::type >
+{
+ return unexpected_type< typename std::decay<E>::type >( v );
+}
+
+/*nsel_constexpr14*/ inline auto
+make_unexpected_from_current_exception() -> unexpected_type< std::exception_ptr >
+{
+ return unexpected_type< std::exception_ptr >( std::current_exception() );
+}
+
+/// in-place tag: construct a value in-place (should come from std::experimental::optional)
+
+struct in_place_t{};
+
+constexpr in_place_t in_place{};
+
+/// unexpect tag, in_place_unexpected tag: construct an error
+
+struct in_place_unexpected_t{};
+
+constexpr in_place_unexpected_t unexpect{};
+constexpr in_place_unexpected_t in_place_unexpected{};
+
+/// expected access error
+
+template< typename E >
+class bad_expected_access : public std::logic_error
+{
+public:
+ typedef E error_type;
+
+ explicit bad_expected_access( error_type error )
+ : logic_error( "bad_expected_access" )
+ , m_error( error )
+ {}
+
+ constexpr error_type const & error() const
+ {
+ return m_error;
+ }
+
+ error_type & error()
+ {
+ return m_error;
+ }
+
+private:
+ error_type m_error;
+};
+
+/// class error_traits
+
+template< typename Error >
+struct error_traits
+{
+ static void rethrow( Error const & e )
+ {
+ throw bad_expected_access<Error>{ e };
+ }
+};
+
+template<>
+struct error_traits< std::exception_ptr >
+{
+ static void rethrow( std::exception_ptr const & e )
+ {
+ std::rethrow_exception( e );
+ }
+};
+
+template<>
+struct error_traits< std::error_code >
+{
+ static void rethrow( std::error_code const & e )
+ {
+ throw std::system_error( e );
+ }
+};
+
+/// class expected
+
+template< typename T, typename E = std::error_code >
+class expected
+{
+public:
+ typedef T value_type;
+ typedef E error_type;
+
+ // constructors
+
+ nsel_REQUIRES_0(
+ std::is_default_constructible<T>::value )
+
+ nsel_constexpr14 expected() noexcept
+ (
+ std::is_nothrow_default_constructible<T>::value
+ )
+ : has_value_( true )
+ {
+ contained.construct_value( value_type() );
+ }
+
+// nsel_REQUIRES_0(
+// std::is_copy_constructible<T>::value &&
+// std::is_copy_constructible<E>::value )
+
+ nsel_constexpr14 expected( expected const & rhs )
+ : has_value_( rhs.has_value_ )
+ {
+ if ( has_value() ) contained.construct_value( rhs.contained.value() );
+ else contained.construct_error( rhs.contained.error() );
+ }
+
+// nsel_REQUIRES_0(
+// std::is_move_constructible<T>::value &&
+// std::is_move_constructible<E>::value )
+
+ nsel_constexpr14 expected( expected && rhs )
+ : has_value_( rhs.has_value_ )
+ {
+ if ( has_value() ) contained.construct_value( std::move( rhs.contained.value() ) );
+ else contained.construct_error( std::move( rhs.contained.error() ) );
+ }
+
+ nsel_REQUIRES_0(
+ std::is_copy_constructible<T>::value )
+
+ nsel_constexpr14 expected( value_type const & rhs )
+ : has_value_( true )
+ {
+ contained.construct_value( rhs );
+ }
+
+ nsel_REQUIRES_0(
+ std::is_move_constructible<T>::value )
+
+ nsel_constexpr14 expected( value_type && rhs ) noexcept
+ (
+ std::is_nothrow_move_constructible<T>::value &&
+ std::is_nothrow_move_constructible<E>::value
+ )
+ : has_value_( true )
+ {
+ contained.construct_value( std::move( rhs ) );
+ }
+
+ template <typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<T, Args&&...>::value ) >
+
+ nsel_constexpr14 explicit expected( in_place_t, Args&&... args )
+ : has_value_( true )
+ {
+ contained.construct_value( std::forward<Args>( args )... );
+ }
+
+ template< typename U, typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<T, std::initializer_list<U>, Args&&...>::value ) >
+
+ nsel_constexpr14 explicit expected( in_place_t, std::initializer_list<U> il, Args&&... args )
+ : has_value_( true )
+ {
+ contained.construct_value( il, std::forward<Args>( args )... );
+ }
+
+ nsel_REQUIRES_0(
+ std::is_copy_constructible<E>::value )
+
+ nsel_constexpr14 expected( unexpected_type<E> const & error )
+ : has_value_( false )
+ {
+ contained.construct_error( error.value() );
+ }
+
+ nsel_REQUIRES_0(
+ std::is_move_constructible<E>::value )
+
+ nsel_constexpr14 expected( unexpected_type<E> && error )
+ : has_value_( false )
+ {
+ contained.construct_error( std::move( error.value() ) );
+ }
+
+ template< typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<E, Args&&...>::value ) >
+
+ nsel_constexpr14 explicit expected( in_place_unexpected_t, Args&&... args )
+ : has_value_( false )
+ {
+ contained.construct_error( std::forward<Args>( args )... );
+ }
+
+ template< typename U, typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<T, std::initializer_list<U>, Args&&...>::value ) >
+
+ nsel_constexpr14 explicit expected( in_place_unexpected_t, std::initializer_list<U> il, Args&&... args )
+ : has_value_( false )
+ {
+ contained.construct_error( il, std::forward<Args>( args )... );
+ }
+
+ // destructor
+
+ ~expected()
+ {
+ if ( has_value() ) contained.destruct_value();
+ else contained.destruct_error();
+ }
+
+ // assignment
+
+// nsel_REQUIRES(
+// std::is_copy_constructible<T>::value &&
+// std::is_copy_assignable<T>::value &&
+// std::is_copy_constructible<E>::value &&
+// std::is_copy_assignable<E>::value )
+
+ expected operator=( expected const & rhs )
+ {
+ expected( rhs ).swap( *this );
+ return *this;
+ }
+
+// nsel_REQUIRES(
+// std::is_move_constructible<T>::value &&
+// std::is_move_assignable<T>::value &&
+// std::is_move_constructible<E>::value &&
+// std::is_move_assignable<E>::value )
+
+ expected & operator=( expected && rhs ) noexcept
+ (
+ std::is_nothrow_move_assignable<T>::value &&
+ std::is_nothrow_move_constructible<T>::value&&
+ std::is_nothrow_move_assignable<E>::value &&
+ std::is_nothrow_move_constructible<E>::value )
+ {
+ expected( std::move( rhs ) ).swap( *this );
+ return *this;
+ }
+
+ template< typename U, nsel_REQUIRES_T(
+ std::is_constructible<T,U>::value &&
+ std::is_assignable<T&, U>::value ) >
+
+ expected & operator=( U && v )
+ {
+ expected( std::forward<U>( v ) ).swap( *this );
+ return *this;
+ }
+
+// nsel_REQUIRES(
+// std::is_copy_constructible<E>::value &&
+// std::is_assignable<E&, E>::value )
+
+ expected & operator=( unexpected_type<E> const & u )
+ {
+ expected( std::move( u ) ).swap( *this );
+ return *this;
+ }
+
+// nsel_REQUIRES(
+// std::is_copy_constructible<E>::value &&
+// std::is_assignable<E&, E>::value )
+
+ expected & operator=( unexpected_type<E> && u )
+ {
+ expected( std::move( u ) ).swap( *this );
+ return *this;
+ }
+
+ template< typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<T, Args&&...>::value ) >
+
+ void emplace( Args &&... args )
+ {
+ expected( in_place, std::forward<Args>(args)... ).swap( *this );
+ }
+
+ template< typename U, typename... Args, nsel_REQUIRES_T(
+ std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value ) >
+
+ void emplace( std::initializer_list<U> il, Args &&... args )
+ {
+ expected( in_place, il, std::forward<Args>(args)... ).swap( *this );
+ }
+
+// nsel_REQUIRES(
+// std::is_move_constructible<T>::value &&
+// std::is_move_constructible<E>::value )
+
+ void swap( expected & rhs ) noexcept
+ (
+ std::is_nothrow_move_constructible<T>::value && noexcept( std::swap( std::declval<T&>(), std::declval<T&>() ) ) &&
+ std::is_nothrow_move_constructible<E>::value && noexcept( std::swap( std::declval<E&>(), std::declval<E&>() ) ) )
+ {
+ using std::swap;
+
+ if ( bool(*this) && bool(rhs) ) { swap( contained.value(), rhs.contained.value() ); }
+ else if ( ! bool(*this) && ! bool(rhs) ) { swap( contained.error(), rhs.contained.error() ); }
+ else if ( bool(*this) && ! bool(rhs) ) { error_type t( std::move( rhs.error() ) );
+ // TBD - ?? rhs.contained.destruct_error();
+ rhs.contained.construct_value( std::move( contained.value() ) );
+ // TBD - ?? contained.destruct_value();
+ contained.construct_error( std::move( t ) );
+ swap( has_value_, rhs.has_value_ ); }
+ else if ( ! bool(*this) && bool(rhs) ) { rhs.swap( *this ); }
+ }
+
+ // observers
+
+ constexpr value_type const * operator ->() const
+ {
+ return assert( has_value() ), contained.value_ptr();
+ }
+
+ value_type * operator ->()
+ {
+ return assert( has_value() ), contained.value_ptr();
+ }
+
+ constexpr value_type const & operator *() const &
+ {
+ return assert( has_value() ), contained.value();
+ }
+
+ value_type & operator *() &
+ {
+ return assert( has_value() ), contained.value();
+ }
+
+ constexpr value_type && operator *() const &&
+ {
+ return assert( has_value() ), std::move( contained.value() );
+ }
+
+ value_type && operator *() &&
+ {
+ return assert( has_value() ), std::move( contained.value() );
+ }
+
+
+ constexpr explicit operator bool() const noexcept
+ {
+ return has_value();
+ }
+
+ constexpr bool has_value() const noexcept
+ {
+ return has_value_;
+ }
+
+ constexpr value_type const & value() const &
+ {
+ return has_value()
+ ? ( contained.value() )
+ : ( error_traits<error_type>::rethrow( contained.error() ), contained.value() );
+ }
+
+ value_type & value() &
+ {
+ return has_value()
+ ? ( contained.value() )
+ : ( error_traits<error_type>::rethrow( contained.error() ), contained.value() );
+ }
+
+ value_type && value() &&
+ {
+ return has_value()
+ ? ( contained.value() )
+ : ( error_traits<error_type>::rethrow( contained.error() ), contained.value() );
+ }
+
+ constexpr error_type const & error() const &
+ {
+ return assert( ! has_value() ), contained.error();
+ }
+
+ error_type & error() &
+ {
+ return assert( ! has_value() ), contained.error();
+ }
+
+ constexpr error_type && error() const &&
+ {
+ return assert( ! has_value() ), std::move( contained.error() );
+ }
+
+ constexpr unexpected_type<E> get_unexpected() const
+ {
+ return make_unexpected( contained.error() );
+ }
+
+ template< typename Ex >
+ bool has_exception() const
+ {
+ return ! has_value() && std::is_base_of< Ex, decltype( get_unexpected().value() ) >::value;
+ }
+
+ template< typename U, nsel_REQUIRES_T(
+ std::is_copy_constructible<T>::value &&
+ std::is_convertible<U&&, T>::value ) >
+
+ value_type value_or( U && v ) const &
+ {
+ return has_value()
+ ? contained.value()
+ : static_cast<T>( std::forward<U>( v ) );
+ }
+
+ template< typename U, nsel_REQUIRES_T(
+ std::is_move_constructible<T>::value &&
+ std::is_convertible<U&&, T>::value ) >
+
+ value_type value_or( U && v ) &&
+ {
+ return has_value()
+ ? std::move( contained.value() )
+ : static_cast<T>( std::forward<U>( v ) );
+ }
+
+ // unwrap()
+
+// template <class U, class E>
+// constexpr expected<U,E> expected<expected<U,E>,E>::unwrap() const&;
+
+// template <class T, class E>
+// constexpr expected<T,E> expected<T,E>::unwrap() const&;
+
+// template <class U, class E>
+// expected<U,E> expected<expected<U,E>, E>::unwrap() &&;
+
+// template <class T, class E>
+// template expected<T,E> expected<T,E>::unwrap() &&;
+
+ // factories
+
+// template <typename Ex, typename F>
+// expected<T,E> catch_exception(F&& f);
+
+// template <typename F>
+// expected<decltype(func(declval<T>())),E> map(F&& func) ;
+
+// template <typename F>
+// ’see below’ bind(F&& func);
+
+// template <typename F>
+// expected<T,E> catch_error(F&& f);
+
+// template <typename F>
+// ’see below’ then(F&& func);
+
+private:
+ bool has_value_;
+ expected_detail::storage_t<T,E> contained;
+};
+
+/// class expected, void specialization
+
+template< typename E >
+class expected<void, E>
+{
+public:
+ typedef void value_type;
+ typedef E error_type;
+
+ template< typename U >
+ struct rebind
+ {
+ typedef expected<U, error_type> type;
+ };
+
+ // constructors
+
+ constexpr expected() noexcept
+ : has_value_( true )
+ {
+ }
+
+ // nsel_REQUIRES_0(
+ // std::is_copy_constructible<E>::value )
+
+ nsel_constexpr14 expected( expected const & rhs )
+ : has_value_( rhs.has_value_ )
+ {
+ if ( ! has_value() ) contained.construct_error( rhs.contained.error() );
+ }
+
+ nsel_REQUIRES_0(
+ std::is_move_constructible<E>::value )
+
+ nsel_constexpr14 expected( expected && rhs ) noexcept
+ (
+ true // TBD - see also non-void specialization
+ )
+ : has_value_( rhs.has_value_ )
+ {
+ if ( ! has_value() ) contained.construct_error( std::move( rhs.contained.error() ) );
+ }
+
+ //nsel_REQUIRES_0(
+ // std::is_default_constructible<E>::value )
+
+ constexpr explicit expected( in_place_t )
+ : has_value_( true )
+ {
+ }
+
+// nsel_REQUIRES(
+// std::is_copy_constructible<E>::value &&
+// std::is_assignable<E&, E>::value )
+
+ nsel_constexpr14 expected( unexpected_type<E> const & error )
+ : has_value_( false )
+ {
+ contained.construct_error( error.value() );
+ }
+
+ // ?? expected( unexpected_type<E> && error )
+
+ template <class Err>
+ nsel_constexpr14 expected( unexpected_type<Err> const & error )
+ : has_value_( false )
+ {
+ contained.construct_error( error.value() );
+ }
+
+ // destructor
+
+ ~expected()
+ {
+ if ( ! has_value() ) contained.destruct_error();
+ }
+
+ // assignment
+
+// nsel_REQUIRES(
+// std::is_copy_constructible<E>::value &&
+// std::is_copy_assignable<E>::value )
+
+ expected & operator=(expected const & rhs )
+ {
+ expected( rhs ).swap( *this );
+ return *this;
+ }
+
+// nsel_REQUIRES(
+// std::is_move_constructible<E>::value &&
+// std::is_move_assignable<E>::value )
+
+ expected & operator=( expected && rhs ) noexcept
+ (
+ std::is_nothrow_move_assignable<E>::value &&
+ std::is_nothrow_move_constructible<E>::value )
+ {
+ expected( std::move( rhs ) ).swap( *this );
+ return *this;
+ }
+
+ void emplace()
+ {}
+
+ // swap
+
+// nsel_REQUIRES(
+// std::is_move_constructible<E>::value )
+
+ void swap( expected & rhs ) noexcept
+ (
+ std::is_nothrow_move_constructible<E>::value && noexcept( std::swap( std::declval<E&>(), std::declval<E&>() ) )
+ )
+ {
+ using std::swap;
+
+ if ( ! bool(*this) && ! bool(rhs) ) { swap( contained.error(), rhs.contained.error() ); }
+ else if ( bool(*this) && ! bool(rhs) ) { contained.construct_error( std::move( rhs.error() ) );
+ swap( has_value_, rhs.has_value_ ); }
+ else if ( ! bool(*this) && bool(rhs) ) { rhs.swap( *this ); }
+ }
+
+ // observers
+
+ constexpr explicit operator bool() const noexcept
+ {
+ return has_value();
+ }
+
+ constexpr bool has_value() const noexcept
+ {
+ return has_value_;
+ }
+
+ void value() const
+ {}
+
+ constexpr error_type const & error() const &
+ {
+ return assert( ! has_value() ), contained.error();
+ }
+
+ error_type & error() &
+ {
+ return assert( ! has_value() ), contained.error();
+ }
+
+ constexpr error_type && error() const &&
+ {
+ return assert( ! has_value() ), std::move( contained.error() );
+ }
+
+ constexpr unexpected_type<error_type> get_unexpected() const
+ {
+ return make_unexpected( contained.error() );
+ }
+
+ template <typename Ex>
+ bool has_exception() const
+ {
+ return ! has_value() && std::is_base_of< Ex, decltype( get_unexpected().value() ) >::value;
+ }
+
+// template constexpr ’see below’ unwrap() const&;
+//
+// template ’see below’ unwrap() &&;
+
+ // factories
+
+// template <typename Ex, typename F>
+// expected<void,E> catch_exception(F&& f);
+//
+// template <typename F>
+// expected<decltype(func()), E> map(F&& func) ;
+//
+// template <typename F>
+// ’see below’ bind(F&& func) ;
+//
+// template <typename F>
+// expected<void,E> catch_error(F&& f);
+//
+// template <typename F>
+// ’see below’ then(F&& func);
+
+private:
+ bool has_value_;
+ expected_detail::storage_t<void,E> contained;
+};
+
+// expected: relational operators
+
+template <typename T, typename E>
+constexpr bool operator==( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return bool(x) != bool(y) ? false : bool(x) == false ? true : *x == *y;
+}
+
+template <typename T, typename E>
+constexpr bool operator!=( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return !(x == y);
+}
+
+template <typename T, typename E>
+constexpr bool operator<( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return (!y) ? false : (!x) ? true : *x < *y;
+}
+
+template <typename T, typename E>
+constexpr bool operator>( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return (y < x);
+}
+
+template <typename T, typename E>
+constexpr bool operator<=( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return !(y < x);
+}
+
+template <typename T, typename E>
+constexpr bool operator>=( expected<T,E> const & x, expected<T,E> const & y )
+{
+ return !(x < y);
+}
+
+// expected: comparison with unexpected_type
+
+template <typename T, typename E>
+constexpr bool operator==( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return (!x) ? x.get_unexpected() == u : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator==( unexpected_type<E> const & u, expected<T,E> const & x )
+{
+ return ( x == u );
+}
+
+template <typename T, typename E>
+constexpr bool operator!=( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return ! ( x == u );
+}
+
+template <typename T, typename E>
+constexpr bool operator!=( unexpected_type<E> const & u, expected<T,E> const & x )
+{
+ return ! ( x == u );
+}
+
+template <typename T, typename E>
+constexpr bool operator<( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return (!x) ? ( x.get_unexpected() < u ) : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator<( unexpected_type<E> const & u, expected<T,E> const & x )
+{
+ return (!x) ? ( u < x.get_unexpected() ) : true ;
+}
+
+template <typename T, typename E>
+constexpr bool operator>( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return ( u < x );
+}
+
+template <typename T, typename E>
+constexpr bool operator>( unexpected_type<E> const & u, expected<T,E> const & x )
+{
+ return ( x < u );
+}
+
+template <typename T, typename E>
+constexpr bool operator<=( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return ! ( u < x );
+}
+
+template <typename T, typename E>
+constexpr bool operator<=( unexpected_type<E> const & u, expected<T,E> const & x)
+{
+ return ! ( x < u );
+}
+
+template <typename T, typename E>
+constexpr bool operator>=( expected<T,E> const & x, unexpected_type<E> const & u )
+{
+ return ! ( u > x );
+}
+
+template <typename T, typename E>
+constexpr bool operator>=( unexpected_type<E> const & u, expected<T,E> const & x )
+{
+ return ! ( x > u );
+}
+
+// expected: comparison with T
+
+template <typename T, typename E>
+constexpr bool operator==( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? *x == v : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator==(T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? v == *x : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator!=( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? *x != v : true;
+}
+
+template <typename T, typename E>
+constexpr bool operator!=( T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? v != *x : true;
+}
+
+template <typename T, typename E>
+constexpr bool operator<( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? *x < v : true;
+}
+
+template <typename T, typename E>
+constexpr bool operator<( T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? v < *x : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator>( T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? *x < v : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator>( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? v < *x : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator<=( T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? ! ( *x < v ) : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator<=( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? ! ( v < *x ) : true;
+}
+
+template <typename T, typename E>
+constexpr bool operator>=( expected<T,E> const & x, T const & v )
+{
+ return bool(x) ? ! ( *x < v ) : false;
+}
+
+template <typename T, typename E>
+constexpr bool operator>=( T const & v, expected<T,E> const & x )
+{
+ return bool(x) ? ! ( v < *x ) : true;
+}
+
+// expected: specialized algorithms
+
+template< typename T, typename E >
+void swap( expected<T,E> & x, expected<T,E> & y ) noexcept( noexcept( x.swap(y) ) )
+{
+ x.swap( y );
+}
+
+template< typename T>
+constexpr auto make_expected( T && v ) -> expected< typename std::decay<T>::type >
+{
+ return expected< typename std::decay<T>::type >( std::forward<T>( v ) );
+}
+
+// expected<void> specialization:
+
+inline auto make_expected() -> expected<void>
+{
+ return expected<void>( in_place );
+}
+
+template< typename T, typename E >
+constexpr auto make_expected_from_error( E e ) -> expected<T, typename std::decay<E>::type>
+{
+ return expected<T, typename std::decay<E>::type>( make_unexpected( e ) );
+}
+
+END_OPENTRACING_ABI_NAMESPACE
+} // namespace opentracing
+
+namespace std {
+
+// expected: hash support
+
+template< typename T, typename E >
+struct hash< opentracing::expected<T,E> >
+{
+ typedef typename hash<T>::result_type result_type;
+ typedef opentracing::expected<T,E> argument_type;
+
+ constexpr result_type operator()(argument_type const & arg) const
+ {
+ return arg ? std::hash<T>{}(*arg) : result_type{};
+ }
+};
+
+// TBD - ?? remove? see spec.
+template< typename T, typename E >
+struct hash< opentracing::expected<T&,E> >
+{
+ typedef typename hash<T>::result_type result_type;
+ typedef opentracing::expected<T&,E> argument_type;
+
+ constexpr result_type operator()(argument_type const & arg) const
+ {
+ return arg ? std::hash<T>{}(*arg) : result_type{};
+ }
+};
+
+// TBD - implement
+// bool(e), hash<expected<void,E>>()(e) shall evaluate to the hashing true;
+// otherwise it evaluates to an unspecified value if E is exception_ptr or
+// a combination of hashing false and hash<E>()(e.error()).
+
+template< typename E >
+struct hash< opentracing::expected<void,E> >
+{
+};
+
+} // namespace std
+
+#undef nsel_REQUIRES
+#undef nsel_REQUIRES_0
+#undef nsel_REQUIRES_T
+
+#endif // OPENTRACING_EXPECTED_LITE_HPP