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62 lines
1.1 KiB
C++
62 lines
1.1 KiB
C++
#ifndef BOOST_LEAF_18ADC47C206611E983ECE95B87D1CC0E
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#define BOOST_LEAF_18ADC47C206611E983ECE95B87D1CC0E
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// Copyright (c) 2018-2019 Emil Dotchevski and Reverge Studios, Inc.
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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#include "_test_ec.hpp"
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template <class T, class E>
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class res
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{
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enum class variant
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{
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value,
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error
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};
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T value_;
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E error_;
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variant which_;
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public:
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res( T const & value ) noexcept:
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value_(value),
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which_(variant::value)
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{
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}
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res( E const & error ) noexcept:
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error_(error),
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which_(variant::error)
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{
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}
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explicit operator bool() const noexcept
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{
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return which_==variant::value;
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}
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T const & value() const
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{
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assert(which_==variant::value);
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return value_;
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}
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E const & error() const
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{
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assert(which_==variant::error);
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return error_;
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}
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};
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namespace boost { namespace leaf {
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template <class T>
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struct is_result_type;
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template <class T, class E>
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struct is_result_type<res<T, E>>: std::true_type
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{
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};
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} }
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#endif
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