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#pragma once
#include <memory>
#include <type_traits>
#include <utility>
namespace mbgl {
namespace util {
class peer {
public:
peer() noexcept : storage(nullptr, noop_deleter) {}
template <class T>
peer(T&& value) noexcept : storage(new std::decay_t<T>(std::forward<T>(value)), cast_deleter<std::decay_t<T>>) {
static_assert(!std::is_same<peer, std::decay_t<T>>::value, "Peer must not wrap itself.");
}
bool has_value() const noexcept { return static_cast<bool>(storage); }
template <class T>
T& get() noexcept { return *reinterpret_cast<T*>(storage.get()); }
private:
template <typename T>
static void cast_deleter(void* ptr) noexcept { delete reinterpret_cast<T*>(ptr); }
static void noop_deleter(void*) noexcept {}
using storage_t = std::unique_ptr<void, void(*)(void*)>;
storage_t storage;
};
} // namespace util
} // namespace mbgl
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