| //===- llvm/ADT/Identity.h - Provide std::identity from C++20 ---*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file provides an implementation of std::identity from C++20. |
| // |
| // No library is required when using these functions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ADT_IDENTITY_H |
| #define LLVM_ADT_IDENTITY_H |
| |
| |
| namespace llvm { |
| |
| // Similar to `std::identity` from C++20. |
| template <class Ty> struct identity { |
| using is_transparent = void; |
| using argument_type = Ty; |
| |
| Ty &operator()(Ty &self) const { |
| return self; |
| } |
| const Ty &operator()(const Ty &self) const { |
| return self; |
| } |
| }; |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_ADT_IDENTITY_H |
