Boost 1.73 Released and other Matters The 1.73.0 release of Boost took up more attention than I had anticipated, but in the end all seemed to go well. Since then I’ve been working through the issues list on GitHub and am now starting to make some headway. I cam across a few other interesting (to me) topics this month. (Possibly) Interesting Asio Things Last month I asked the question, “Is it possible to write an asynchronous composed operation entirely as a lambda?”. This month I went a little further with two items that interested me. The first is whether asio’s async_compose can be adapted so that we can implement a complex composed operation involving more than one IO object easily using the asio faux coroutine mechanism. The second was whether is was possible to easily implement an async future in Asio. Async Asio Future Here is my motivating use case: auto p = async::promise<std::string>(); auto f = p.get_future(); // long-running process starts which will yield a string start_something(std::move(p)); // wait on the future f.async_wait([](some_result_type x) { // use the x }); // or auto str = co_await f.async_wait(net::use_awaitable); // or shorthand auto str = co_await f(); The salient points here...

Boost 1.73 New Library StaticString: A dynamically resizable string of characters with compile-time fixed capacity and contiguous embedded storage, from Krystian Stasiowski and Vinnie Falco. Boost Release Notes

The Rundown Due to the COVID-19 pandemic, my classes have been moved online. It’s certainly an interesting way to teach, but admittedly I can’t say it’s enjoyable or effective. However, it has given me a lot of time to work on various projects, which is a reasonable trade-off (at least in my opinion). I got quite a bit done this month due to the substantial increase in leisure time, and was able to work on several projects that previously didn’t fit into my schedule. Boost.StaticString I spent the first few days of March putting the finishing touches on Boost.StaticString in preparation for the release of Boost 1.73.0, mostly consisting of housekeeping tasks, but also some bug fixes for certain compiler configurations. In particular, a problem arose with GCC 5 regarding its constexpr support, two of which impede using basic_static_string during constant evaluation: throw expressions, and non-static member functions whose return type is the class they are a member of. With respect to the former, consider the following: constexpr int throw_not_evaluated(bool flag) { if (flag) throw 1; return 0; } constexpr int const_eval = throw_not_evaluated(false); View this on Godbolt It is helpful to first establish what the standard has to say...

Coding in the time of a Pandemic It has been an interesting month, there having been the minor distraction of a lockdown of our little country. The borders with Spain and France were closed about three weeks ago and all residents have been asked to stay at home other than to buy groceries or walk their dogs. Fortunately I have dogs so I at least have a legitimate reason to see the sun. One of the advantages of living in a tiny country is that the government has been able to secure the supply of 150,000 COVID-19 testing kits, which represents two tests per resident. They are also working on supplying every resident with masks for use when shopping. I am hoping to report in my next blog that we are allowed outside subject to a negative test and the wearing of a mask and gloves. Fortunately, until today, our internet has been uninterrupted. Communication with my friends and colleagues at the C++ Alliance and the wider developer community has continued. Boost Release The Boost 1.73 release is imminent. Thus much of my focus in the latter half of the month has been on addressing any remaining issues in Beast...

Introduction I’m a first-year university student at the University of Connecticut pursuing a degree in Computer Science. I joined The C++ Alliance near the end of January as a part-time Staff Engineer at the recommendation of Vinnie, who has been mentoring me for the past several months. I’ve been programming in C++ for around 2 years now, with an interest in library development and standardization. My original reasoning for choosing C++ over other languages was a little misguided, being that it was generally regarded as a difficult language, and I liked the challenge. Prior to this, I had dabbled in the language a little bit, but I really didn’t get into it until I discovered the existence of the standard. A language with explicitly defined semantics, all specified in a document that is difficult to parse sounded very appealing to me, and thus I embarked on my journey to learn everything about it that I could. If you were to ask me what I like most about it now, it would probably be a tie between the “you don’t pay for what you don’t use” principle and zero cost generics. With regard to standardization, I do a lot of standardese...