29 lines
645 B
C++
29 lines
645 B
C++
// Copyright 2020 The Chromium Authors
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef BASE_FUNCTIONAL_IDENTITY_H_
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#define BASE_FUNCTIONAL_IDENTITY_H_
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#include <utility>
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namespace base {
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// Implementation of C++20's std::identity.
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//
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// Reference:
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// - https://en.cppreference.com/w/cpp/utility/functional/identity
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// - https://wg21.link/func.identity
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struct identity {
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template <typename T>
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constexpr T&& operator()(T&& t) const noexcept {
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return std::forward<T>(t);
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}
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using is_transparent = void;
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};
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} // namespace base
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#endif // BASE_FUNCTIONAL_IDENTITY_H_
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