text: //
  // Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2020
  //
  // 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)
  //
  #pragma once
  
  #include "td/utils/common.h"
  #include "td/utils/StringBuilder.h"
  #include "td/utils/tl_helpers.h"
  
  #include <functional>
  #include <type_traits>
  
  namespace td {
  
  class BackgroundId {
    int64 id = 0;
  
   public:
    BackgroundId() = default;
  
    explicit BackgroundId(int64 background_id) : id(background_id) {
    }
    template <class T, typename = std::enable_if_t<std::is_convertible<T, int64>::value>>
    BackgroundId(T background_id) = delete;
  
    int64 get() const {
      return id;
    }
  
    bool operator==(const BackgroundId &other) const {
      return id == other.id;
    }
  
    bool operator!=(const BackgroundId &other) const {
      return id != other.id;
    }
  
    bool is_valid() const {
      return id != 0;
    }
  
    template <class StorerT>
    void store(StorerT &storer) const {
      td::store(id, storer);
    }
  
    template <class ParserT>
    void parse(ParserT &parser) {
      td::parse(id, parser);
    }
  };
  
  struct BackgroundIdHash {
    std::size_t operator()(BackgroundId background_id) const {
      return std::hash<int64>()(background_id.get());
    }
  };
  
  inline StringBuilder &operator<<(StringBuilder &string_builder, BackgroundId background_id) {
    return string_builder << "background " << background_id.get();
  }
  
  }  // namespace td
  