GSL/include/final_action.h
2015-10-01 08:34:10 -04:00

72 lines
2.0 KiB
C++

///////////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2015 Microsoft Corporation. All rights reserved.
//
// This code is licensed under the MIT License (MIT).
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
///////////////////////////////////////////////////////////////////////////////
#pragma once
#ifndef GSL_FINAL_ACTION_H
#define GSL_FINAL_ACTION_H
#ifdef _MSC_VER
// VS 2013 workarounds
#if _MSC_VER <= 1800
// noexcept is not understood
#define noexcept /* nothing */
#endif // _MSC_VER <= 1800
#endif // _MSC_VER
namespace gsl
{
//
// GSL.util: Utilities
//////////////////////
// This component is a `gsl` utility that allows you to ensure that an act
// gets performed at the end of a scope
template <class F>
class final_action
{
public:
explicit final_action(F f) noexcept : f_(std::move(f)), invoke_(true) {}
final_action(final_action&& other) noexcept : f_(std::move(other.f_)), invoke_(true) { other.invoke_ = false; }
~final_action() noexcept { if (invoke_) f_(); }
private:
final_action(const final_action&) = delete;
final_action& operator=(const final_action&) = delete;
private:
F f_;
bool invoke_;
};
//
// Function name: finally
//
// This is convenience function to generate a final_action
//
template <class F>
final_action<F> finally(const F& f) noexcept { return final_action<F>(f); }
template <class F>
final_action<F> finally(F&& f) noexcept { return final_action<F>(std::forward<F>(f)); }
} // close namespace gsl
#endif // GSL_FINAL_ACTION_H