virtualx-engine/thirdparty/openxr/src/common/extra_algorithms.h
2024-01-09 11:47:45 +11:00

47 lines
1.5 KiB
C++

// Copyright (c) 2017-2024, The Khronos Group Inc.
// Copyright (c) 2017-2019 Valve Corporation
// Copyright (c) 2017-2019 LunarG, Inc.
// Copyright (c) 2019 Collabora, Ltd.
//
// SPDX-License-Identifier: Apache-2.0 OR MIT
//
// Initial Author: Rylie Pavlik <rylie.pavlik@collabora.com>
//
/*!
* @file
*
* Additional functions along the lines of the standard library algorithms.
*/
#pragma once
#include <algorithm>
#include <vector>
/// Like std::remove_if, except it works on associative containers and it actually removes this.
///
/// The iterator stuff in here is subtle - .erase() invalidates only that iterator, but it returns a non-invalidated iterator to the
/// next valid element which we can use instead of incrementing.
template <typename T, typename Pred>
static inline void map_erase_if(T &container, Pred &&predicate) {
for (auto it = container.begin(); it != container.end();) {
if (predicate(*it)) {
it = container.erase(it);
} else {
++it;
}
}
}
/*!
* Moves all elements matching the predicate to the end of the vector then erases them.
*
* Combines the two parts of the erase-remove idiom to simplify things and avoid accidentally using the wrong erase overload.
*/
template <typename T, typename Alloc, typename Pred>
static inline void vector_remove_if_and_erase(std::vector<T, Alloc> &vec, Pred &&predicate) {
auto b = vec.begin();
auto e = vec.end();
vec.erase(std::remove_if(b, e, std::forward<Pred>(predicate)), e);
}