SubjectRef.h

浏览该文件的文档.

#pragma once
 
#include "common/Identity.h"
 
#include <cstddef>
 
namespace eve {
 
class SubjectRef {
public:
    SubjectRef() = default;
 
    [[nodiscard]] static SubjectRef fromPersistentId(PersistentId id) noexcept { return SubjectRef(id); }
 
    [[nodiscard]] static SubjectRef nil() noexcept { return {}; }
 
    [[nodiscard]] bool isValid() const noexcept { return !id_.isNil(); }
 
    [[nodiscard]] PersistentId persistentId() const noexcept { return id_; }
 
    [[nodiscard]] std::string format() const { return id_.format(); }
 
    friend bool operator==(const SubjectRef&, const SubjectRef&) noexcept = default;
 
private:
    explicit SubjectRef(PersistentId id) noexcept : id_(id) {}
 
    PersistentId id_;
};
 
}  // namespace eve
 
namespace std {
 
template <>
struct hash<eve::SubjectRef> {
    size_t operator()(const eve::SubjectRef& value) const noexcept {
        return static_cast<size_t>(value.persistentId().hash());
    }
};
 
}  // namespace std