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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_DEFAULT_RESOURCE_HPP
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#ifndef BOOST_JSON_DEFAULT_RESOURCE_HPP
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#define BOOST_JSON_DEFAULT_RESOURCE_HPP
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#define BOOST_JSON_DEFAULT_RESOURCE_HPP
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#include <boost/json/detail/config.hpp>
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#include <boost/json/detail/config.hpp>
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#include <boost/container/pmr/memory_resource.hpp>
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#include <boost/container/pmr/memory_resource.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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#ifdef _MSC_VER
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#ifdef _MSC_VER
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#pragma warning(push)
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#pragma warning(push)
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#pragma warning(disable: 4251) // class needs to have dll-interface to be used by clients of class
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#pragma warning(disable: 4251) // class needs to have dll-interface to be used by clients of class
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#pragma warning(disable: 4275) // non dll-interface class used as base for dll-interface class
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#pragma warning(disable: 4275) // non dll-interface class used as base for dll-interface class
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#endif
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#endif
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// A simple memory resource that uses operator new and delete.
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// A simple memory resource that uses operator new and delete.
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class
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class
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    BOOST_SYMBOL_VISIBLE
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    BOOST_SYMBOL_VISIBLE
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    BOOST_JSON_DECL
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    BOOST_JSON_DECL
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default_resource final
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default_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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    union holder;
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    union holder;
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#ifndef BOOST_JSON_WEAK_CONSTINIT
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#ifndef BOOST_JSON_WEAK_CONSTINIT
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# ifndef BOOST_JSON_NO_DESTROY
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# ifndef BOOST_JSON_NO_DESTROY
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    static holder instance_;
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    static holder instance_;
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# else
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# else
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    BOOST_JSON_NO_DESTROY
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    BOOST_JSON_NO_DESTROY
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    static default_resource instance_;
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    static default_resource instance_;
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# endif
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# endif
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#endif
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#endif
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public:
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public:
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    static
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    static
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    container::pmr::memory_resource*
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    container::pmr::memory_resource*
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    get() noexcept
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    get() noexcept
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    {
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    {
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    #ifdef BOOST_JSON_WEAK_CONSTINIT
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    #ifdef BOOST_JSON_WEAK_CONSTINIT
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        static default_resource instance_;
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        static default_resource instance_;
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    #endif
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    #endif
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        return reinterpret_cast<memory_resource*>(
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        return reinterpret_cast<memory_resource*>(
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            reinterpret_cast<std::uintptr_t*>(
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            reinterpret_cast<std::uintptr_t*>(
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                &instance_));
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                &instance_));
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    }
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    }
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    ~default_resource();
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    ~default_resource();
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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 n,
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        std::size_t n,
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        std::size_t) override;
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        std::size_t) override;
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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* p,
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        void* p,
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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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    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) const noexcept override;
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        memory_resource const& mr) const noexcept override;
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};
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};
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#ifdef _MSC_VER
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#ifdef _MSC_VER
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#pragma warning(pop)
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#pragma warning(pop)
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#endif
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#endif
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union default_resource::
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union default_resource::
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    holder
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    holder
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{
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{
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#ifndef BOOST_JSON_WEAK_CONSTINIT
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#ifndef BOOST_JSON_WEAK_CONSTINIT
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    constexpr
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    constexpr
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#endif
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#endif
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    holder()
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    holder()
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        : mr()
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        : mr()
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    {
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    {
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    }
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    }
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    ~holder()
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    ~holder()
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    {
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    {
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    }
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    }
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    default_resource mr;
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    default_resource mr;
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};
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};
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} // detail
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} // detail
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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