unioil-loyalty-rn-app/ios/Pods/Flipper-Boost-iOSX/boost/json/memory_resource.hpp

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//
// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
//
// Distributed under 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)
//
// Official repository: https://github.com/boostorg/json
//
#ifndef BOOST_JSON_MEMORY_RESOURCE_HPP
#define BOOST_JSON_MEMORY_RESOURCE_HPP
#include <boost/json/detail/config.hpp>
#ifdef BOOST_JSON_STANDALONE
# if __has_include(<memory_resource>)
# include <memory_resource>
# ifndef __cpp_lib_memory_resource
# error Support for std::memory_resource is required to use Boost.JSON standalone
# endif
# elif __has_include(<experimental/memory_resource>)
# include <experimental/memory_resource>
# warning Support for std::memory_resource is required to use Boost.JSON standalone, using std::experimental::memory_resource as fallback
# else
# error Header <memory_resource> is required to use Boost.JSON standalone
# endif
#else
# include <boost/container/pmr/memory_resource.hpp>
# include <boost/container/pmr/polymorphic_allocator.hpp>
#endif
BOOST_JSON_NS_BEGIN
#ifdef BOOST_JSON_DOCS
/** The type of memory resource used by the library.
This type alias is set depending
on how the library is configured:
@par Use with Boost
If the macro `BOOST_JSON_STANDALONE` is
not defined, this type will be an alias
for `boost::container::pmr::memory_resource`.
Compiling a program using the library will
require Boost, and a compiler conforming
to C++11 or later.
@par Use without Boost
If the macro `BOOST_JSON_STANDALONE` is
defined, this type will be an alias
for `std::pmr::memory_resource`.
Compiling a program using the library will
require only a compiler conforming to C++17
or later.
@see https://en.cppreference.com/w/cpp/memory/memory_resource
*/
class memory_resource
{
};
/** The type of polymorphic allocator used by the library.
This type alias is set depending
on how the library is configured:
@par Use with Boost
If the macro `BOOST_JSON_STANDALONE` is
not defined, this type will be an alias template
for `boost::container::pmr::polymorphic_allocator`.
Compiling a program using the library will
require Boost, and a compiler conforming
to C++11 or later.
@par Use without Boost
If the macro `BOOST_JSON_STANDALONE` is
defined, this type will be an alias template
for `std::pmr::polymorphic_allocator`.
Compiling a program using the library will
require only a compiler conforming to C++17
or later.
@see https://en.cppreference.com/w/cpp/memory/polymorphic_allocator
*/
template<class T>
class polymorphic_allocator;
// VFALCO Bug: doc toolchain won't make this a ref
//using memory_resource = __see_below__;
#elif defined(BOOST_JSON_STANDALONE)
# if __has_include(<memory_resource>)
using memory_resource = std::pmr::memory_resource;
template<class T>
using polymorphic_allocator =
std::pmr::polymorphic_allocator<T>;
# else
using memory_resource = std::experimental::pmr::memory_resource;
template<class T>
using polymorphic_allocator =
std::experimental::pmr::polymorphic_allocator<T>;
# endif
#else
using memory_resource = boost::container::pmr::memory_resource;
template<class T>
using polymorphic_allocator =
boost::container::pmr::polymorphic_allocator<T>;
#endif
/** Return true if a memory resource's deallocate function has no effect.
This metafunction may be specialized to indicate to
the library that calls to the `deallocate` function of
a @ref memory_resource have no effect. The implementation
will elide such calls when it is safe to do so. By default,
the implementation assumes that all memory resources
require a call to `deallocate` for each memory region
obtained by calling `allocate`.
@par Example
This example specializes the metafuction for `my_resource`,
to indicate that calls to deallocate have no effect:
@code
// Forward-declaration for a user-defined memory resource
struct my_resource;
// It is necessary to specialize the template from
// inside the namespace in which it is declared:
namespace boost {
namespace json {
template<>
struct is_deallocate_trivial< my_resource >
{
static constexpr bool value = true;
};
} // namespace json
} // namespace boost
@endcode
It is usually not necessary for users to check this trait.
Instead, they can call @ref storage_ptr::is_deallocate_trivial
to determine if the pointed-to memory resource has a trivial
deallocate function.
@see
@ref memory_resource,
@ref storage_ptr
*/
template<class T>
struct is_deallocate_trivial
{
/** A bool equal to true if calls to `T::do_deallocate` have no effect.
The primary template sets `value` to false.
*/
static constexpr bool value = false;
};
BOOST_JSON_NS_END
#endif