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// Copyright 2014 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef LIBBRILLO_BRILLO_MAP_UTILS_H_
#define LIBBRILLO_BRILLO_MAP_UTILS_H_
#include <map>
#include <set>
#include <utility>
#include <vector>
namespace brillo {
// Given an STL map, returns a set containing all keys from the map.
template<typename T>
inline std::set<typename T::key_type> GetMapKeys(const T& map) {
std::set<typename T::key_type> keys;
for (const auto& pair : map)
keys.insert(keys.end(), pair.first); // Map keys are already sorted.
return keys;
}
// Given an STL map, returns a vector containing all keys from the map.
// The keys in the vector are sorted.
template<typename T>
inline std::vector<typename T::key_type> GetMapKeysAsVector(const T& map) {
std::vector<typename T::key_type> keys;
keys.reserve(map.size());
for (const auto& pair : map)
keys.push_back(pair.first);
return keys;
}
// Given an STL map, returns a vector containing all values from the map.
template<typename T>
inline std::vector<typename T::mapped_type> GetMapValues(const T& map) {
std::vector<typename T::mapped_type> values;
values.reserve(map.size());
for (const auto& pair : map)
values.push_back(pair.second);
return values;
}
// Given an STL map, returns a vector of key-value pairs from the map.
template<typename T>
inline std::vector<std::pair<typename T::key_type, typename T::mapped_type>>
MapToVector(const T& map) {
std::vector<std::pair<typename T::key_type, typename T::mapped_type>> vector;
vector.reserve(map.size());
for (const auto& pair : map)
vector.push_back(pair);
return vector;
}
// Given an STL map, returns the value associated with a given key or a default
// value if the key is not present in the map.
template<typename T>
inline typename T::mapped_type GetOrDefault(
const T& map,
typename T::key_type key,
const typename T::mapped_type& def) {
typename T::const_iterator it = map.find(key);
if (it == map.end())
return def;
return it->second;
}
} // namespace brillo
#endif // LIBBRILLO_BRILLO_MAP_UTILS_H_