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[cgal-discuss] result_of deprecation from c++20 workaround (PR #3846)

From: Ahmed Essam <>
To:
Subject: [cgal-discuss] result_of deprecation from c++20 workaround (PR #3846)
Date: Fri, 28 Feb 2020 20:25:11 +0200
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Hi all,

I'm Ahmed Essam, and I'm interested in applying for GSoC with you this year.

Regarding PR #3846. As I understand it, the main blocker is the deprecation of `std::result_of` from C++20 in favor of `std::invoke_result`. I think there is a workaround that would work with both C++11 and C++20 when the removal happens. The main idea comes from this blogpost https://devblogs.microsoft.com/oldnewthing/20190710-00/?p=102678.

We will use SFINAE to choose `std::invoke_of` if available, otherwise, choose `std::result_of`. I'm not sure is the mapping of the functionalities here covers all cases, but I think it's worth trying. Please find the code snippet below:

https://gist.github.com/theartful/3dd554239743b4489b2356058f12a432

If you think this might work, I can make a PR for it.

Thanks,

Ahmed Essam

[cgal-discuss] result_of deprecation from c++20 workaround (PR #3846), Ahmed Essam, 02/28/2020
- Re: [cgal-discuss] result_of deprecation from c++20 workaround (PR #3846), Marc Glisse, 02/28/2020
  - Re: [cgal-discuss] result_of deprecation from c++20 workaround (PR #3846), Ahmed Essam, 02/28/2020

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[cgal-discuss] result_of deprecation from c++20 workaround (PR #3846)