CppCon 2016: Vittorio Romeo “Implementing `static` control flow in C++14'

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There has always been great interest in imperative compile-time control flow: as an example, consider all the existing `static_if` proposals and the recently accepted `constexpr_if` construct for C++17.

What if you were told that it is actually possible to implement imperative control flow in C++14?

In this tutorial, the implementation and design of a compile-time `static_if` branching construct and of a compile-time `static_for` iteration construct will be shown and analyzed. These constructs will then be compared to traditional solutions and upcoming C++17 features, examining advantages and drawbacks.
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Vittorio Romeo
Bloomberg LP
Software Engineer
London, UK
Vittorio Romeo is an Italian 21 year old Computer Science student at "Università degli Studi di Messina". He began programming at a very young age and is now a C++ enthusiast. While following the evolution of the C++ standard and embracing the newest features, he worked on several open-source projects, including modern general-purpose libraries and free cross-platform indie games. Vittorio is an active member of the C++ community: he participated as a speaker at CppCon 2014/2015, ++it Florence 2015 and at his local Linux Day 2013/2014 events, as a Student/Volunteer at C++Now 2015, and as part of Meeting C++ 2015's student program. He currently maintains a YouTube channel featuring well-received modern C++11 and C++14 tutorials. When he's not writing code, Vittorio enjoys weightlifting and fitness-related activities, competitive/challenging computer gaming and good scifi movies/TV-series.
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[IvanBudiselic]

Sad to see people disliking. Keep on rocking, Vittorio!

[Fetrovsky]

Thank you for saying STD. So much "stood" is driving me crazy.

[sanjuuyonsai]

31:41 You didn't mention one key point why this works.
The n that is passed to the lambda is not an integer value or some non-type template argument, it is an instance of std::integral_constant. The reason you can use it as a constant expression in buffer<n> to specify the buffer size is because integral_constant has a constexpr cast operator to the integer type it wraps, returning its wrapped value. I was pretty amazed that this works.

[worldsender]

When you talked about why we can't use [&x]{...} I wondered, to make it more useable with multiple variables you could pass in a dummy-variable instead and just capture everything by reference. Then every lambda would just be [&](auto){...} and the call would be with any dummy value - the compiler optimizing it away naturally. But that is of course a problem of the user.

[dawikur]

Unregistered Sublime? Not cool, not cool.