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//
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//
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// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
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// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
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//
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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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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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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//
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// Official repository: https://github.com/boostorg/json
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// Official repository: https://github.com/boostorg/json
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//
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//
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#ifndef BOOST_JSON_IMPL_NULL_RESOURCE_IPP
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#ifndef BOOST_JSON_IMPL_NULL_RESOURCE_IPP
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#define BOOST_JSON_IMPL_NULL_RESOURCE_IPP
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#define BOOST_JSON_IMPL_NULL_RESOURCE_IPP
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#include <boost/json/null_resource.hpp>
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#include <boost/json/null_resource.hpp>
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#include <boost/throw_exception.hpp>
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#include <boost/throw_exception.hpp>
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namespace boost {
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namespace boost {
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namespace json {
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namespace json {
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namespace detail {
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namespace detail {
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/** A resource which always fails.
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/** A resource which always fails.
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    This memory resource always throws the exception
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    This memory resource always throws the exception
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    `std::bad_alloc` in calls to `allocate`.
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    `std::bad_alloc` in calls to `allocate`.
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*/
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*/
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class null_resource final
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class null_resource final
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    : public container::pmr::memory_resource
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    : public container::pmr::memory_resource
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{
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{
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public:
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public:
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    /// Copy constructor (deleted)
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    /// Copy constructor (deleted)
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    null_resource(
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    null_resource(
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        null_resource const&) = delete;
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        null_resource const&) = delete;
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    /// Copy assignment (deleted)
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    /// Copy assignment (deleted)
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    null_resource& operator=(
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    null_resource& operator=(
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        null_resource const&) = delete;
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        null_resource const&) = delete;
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    /** Constructor
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    /** Constructor
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        This constructs the resource.
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        This constructs the resource.
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        @par Complexity
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        @par Complexity
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        Constant.
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        Constant.
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        @par Exception Safety
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        @par Exception Safety
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        No-throw guarantee.
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        No-throw guarantee.
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    */
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    */
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    /** @{ */
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    /** @{ */
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    null_resource() noexcept = default;
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    null_resource() noexcept = default;
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protected:
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protected:
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    void*
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    void*
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    do_allocate(
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    do_allocate(
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        std::size_t,
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        std::size_t,
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        std::size_t) override
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        std::size_t) override
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    {
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    {
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        throw_exception( std::bad_alloc(), BOOST_CURRENT_LOCATION );
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        throw_exception( std::bad_alloc(), BOOST_CURRENT_LOCATION );
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    }
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    }
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    void
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    void
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    do_deallocate(
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    do_deallocate(
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        void*,
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        void*,
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        std::size_t,
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        std::size_t,
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        std::size_t) override
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        std::size_t) override
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    {
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    {
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        // do nothing
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        // do nothing
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    }
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    }
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    bool
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    bool
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    do_is_equal(
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    do_is_equal(
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        memory_resource const& mr
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        memory_resource const& mr
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            ) const noexcept override
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            ) const noexcept override
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    {
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    {
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        return this == &mr;
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        return this == &mr;
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    }
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    }
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};
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};
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} // detail
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} // detail
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container::pmr::memory_resource*
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container::pmr::memory_resource*
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get_null_resource() noexcept
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get_null_resource() noexcept
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{
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{
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    static detail::null_resource mr;
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    static detail::null_resource mr;
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    return &mr;
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    return &mr;
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}
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}
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} // namespace json
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} // namespace json
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} // namespace boost
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} // namespace boost
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#endif
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#endif