C++ Special Member Function Guidelines--Jonathan Müller
Short and sweet.
C++ Special Member Function Guidelines
by Jonathan Müller
From the article:
The C++ special member functions are...
Articles & Books
Quick Q: Implicit conversion and operator overload
Quick A: it tries to convert to int.
Recently on SO:
Implicit conversion and operator overload
In comparing the conversions needed by different overloaded functions, a "promotion" is considered a better conversion sequence than a standard "conversion". Every arithmetic type can promote to at most one other type. (Promotions are also used when passing an argument to a C-style variadic function like printf. The unary + operator can be used to force a promotion of an arithmetic expression, like +n.)
For integer types which are not character types or bool, the promoted type is:
- If int can represent all the values of the original type, then int;
- Otherwise, if unsigned int can represent all the values of the original type, then unsigned int;
- Otherwise, the original type itself (promotion does nothing)
In your example, when comparing the overloaded functions, an "exact match" would be best, but there is no function taking exactly int8_t (or int8_t& or const int8_t&). The promoted type of uint8_t is int, since it's required to support a range much larger than 0-255. And apparently on your system, int32_t is an alias for int, so the function void f(int32_t); requires only a promotion on the argument. The other functions are all viable, but require an integer conversion on the argument. So void f(int32_t); is considered the best overload.
So the technical answer to the question is that it is implementation specific, but only because of the relationship between int and the <cstdint> types, not because of the overload resolution rules.
Kona: A trip report--Corentin Jabot
Did you go?
Kona: A trip report
by Corentin Jabot
From the article:
I was lucky enough to participate in a third wg21 committee meeting in a row, this time in Kona, Hawaii, a mere 13000 kilometers away...
20 years of extending C++: What can we learn? - David Millington - Meeting C++ 2018
What can you learn, when you've wrote Tools for C++ for 20 years?
20 years of extending C++: What can we learn?
by David Millington
Lambdas: From C++11 to C++20, Part 1--Bartlomiej Filipek
Not so old, but already an interesting history.
Lambdas: From C++11 to C++20, Part 1
by Bartlomiej Filipek
From the article:
Lambda expressions are one of the most powerful additions to C++11, and they continue to evolve with each new C++ language standard. In this article, we’ll go through history and see the evolution of this crucial part of modern C++.
C++ User Group Meetings in March
The monthly overview on upcoming C++ User Group meetings by Meeting C++
C++ USer Group Meetings in March 2019
by Jens Weller
From the article
The monthly overview of upcoming C++ User Group meetings! Lots of groups already announced their meetings, if your group is not in the list, they might announce later.
Want to speak at a User Group? Use the contact form to reach out to several User Groups that you'd be able to visit for a talk!
There are 4 new C++ User Groups...
Overload 149 is now available
ACCU’s Overload journal of February 2019 is out. It contains the following C++ related articles.
Overload 149 is now available
From the journal:
Rip It Up and Start Again.
Some things can be resurrected, others cannot. Frances Buontempo wonders when we need to repent and start over.5 Big Fat Reasons Why Mutexes Suck Big Time.
Mutable shared state in multithreaded code is often protected by mutexes. Sergey Ignatchenko reminds us that Re-Actors can avoid many of the problems.A Small Universe.
Writing a programming language is a hot topic. Deák Ferenc shows us how he wrote a compiler for bytecode callable from C++.QM Bites: Understand Windows Operating-System Identification Preprocessor Macros.
Quality matters and bite sized articles help. Matthew Wilson returns with a QM Bites.A Thorough Introduction to Distributed Systems.
What is a distributed system, and why is it so complicated? Stanislav Kozlovski explains.Don’t Use std::endl.
How do you add a new line in C++? Chris Sharpe suggests std::endl is a tiny utility that’s more trouble than it’s worth.
Cpp On Sea 2019 Trip Report--Arne Mertz
Were you there?
Cpp On Sea 2019 Trip Report
by Arne Mertz
From the article:
From February 3rd through February 6th I have been in Folkestone, UK, to visit the first C++ On Sea conference.
There must be something in the water on that island that enables them to organize fantastic conferences like ACCUConf and, since this year, C++ On Sea.
C++ On Sea is definitely the best conference I have ever been to, and here’s a little glimpse why I think so...
2 Lines Of Code and 3 C++17 Features - The overload Pattern--Bartlomiej Filipek
Proof that you can do more!
2 Lines Of Code and 3 C++17 Features - The overload Pattern
by Bartlomiej Filipek
From the article:
While I was doing research for my book and blog posts about C++17 several times I stumbled upon this pattern for visitation of std::variant:
template<class... Ts> struct overload : Ts... { using Ts::operator()...; }; template<class... Ts> overload(Ts...) -> overload<Ts...>; std::variant<int, float> intFloat { 0.0f }; std::visit(overload( [](const int& i) { ... }, [](const float& f) { ... }, ), intFloat; );With the above pattern, you can provide separate lambdas “in-place” for visitation.
It’s just two lines of compact C++ code, but it packs a few interesting concepts.
Let’s see how this thing works and go through the three new C++17 features that enable this one by one.
Why You Should Use std::for_each over Range-based For Loops--Jon Kalb
What do you think?
Why You Should Use std::for_each over Range-based For Loops
by Jon Kalb
From the article:
I’d like start by thanking Jonathan for creating and maintaining the Fluent{C++} blog, for the conversations that it spawns, and for letting me contribute with this guest post. Jonathan has invited me to add my thoughts on his previous posting, Is std::for_each obsolete?