cxx20_erase_vector.h (1506B)
1 // Copyright 2021 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_CONTAINERS_CXX20_ERASE_VECTOR_H_ 6 #define BASE_CONTAINERS_CXX20_ERASE_VECTOR_H_ 7 8 #include <algorithm> 9 #include <iterator> 10 #include <vector> 11 12 namespace base { 13 14 // Erase/EraseIf are based on C++20's uniform container erasure API: 15 // - https://eel.is/c++draft/libraryindex#:erase 16 // - https://eel.is/c++draft/libraryindex#:erase_if 17 // They provide a generic way to erase elements from a container. 18 // The functions here implement these for the standard containers until those 19 // functions are available in the C++ standard. 20 // Note: there is no std::erase for standard associative containers so we don't 21 // have it either. 22 23 template <class T, class Allocator, class Value> 24 size_t Erase(std::vector<T, Allocator>& container, const Value& value) { 25 auto it = std::remove(container.begin(), container.end(), value); 26 size_t removed = static_cast<size_t>(std::distance(it, container.end())); 27 container.erase(it, container.end()); 28 return removed; 29 } 30 31 template <class T, class Allocator, class Predicate> 32 size_t EraseIf(std::vector<T, Allocator>& container, Predicate pred) { 33 auto it = std::remove_if(container.begin(), container.end(), pred); 34 size_t removed = static_cast<size_t>(std::distance(it, container.end())); 35 container.erase(it, container.end()); 36 return removed; 37 } 38 39 } // namespace base 40 41 #endif // BASE_CONTAINERS_CXX20_ERASE_VECTOR_H_