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/*
* Copyright 2018 Google
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_IMMUTABLE_SORTED_MAP_BASE_H_
#define FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_IMMUTABLE_SORTED_MAP_BASE_H_
#include <cstdint>
namespace firebase {
namespace firestore {
namespace immutable {
namespace impl {
/**
* A base class for implementing sorted maps, containing types and constants
* that don't depend upon the template parameters to the main class.
*
* Note that this exists as a base class rather than as just a namespace in
* order to make it possible for users of the SortedMap classes to avoid needing
* to declare storage for each instantiation of the template.
*/
class SortedMapBase {
public:
/**
* The type of size() methods on immutable collections. Note:
* * This is not size_t specifically to save space in the TreeSortedMap
* implementation.
* * This remains unsigned for straightforward casting to size_t.
*/
using size_type = uint32_t;
/**
* The maximum size of an ArraySortedMap.
*
* This is the size threshold where we use a tree backed sorted map instead of
* an array backed sorted map. This is a more or less arbitrary chosen value,
* that was chosen to be large enough to fit most of object kind of Firebase
* data, but small enough to not notice degradation in performance for
* inserting and lookups. Feel free to empirically determine this constant,
* but don't expect much gain in real world performance.
*/
// TODO(wilhuff): actually use this for switching implementations.
static constexpr size_type kFixedSize = 25;
/**
* A sentinel return value that indicates not found. Functionally similar to
* std::string::npos.
*/
static constexpr size_type npos = static_cast<size_type>(-1);
};
} // namespace impl
} // namespace immutable
} // namespace firestore
} // namespace firebase
#endif // FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_IMMUTABLE_SORTED_MAP_BASE_H_
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