More C++ Idioms -- WikiBooks

This is a catalog of reusable pieces of C++ knowledge, similar to the book on design patterns by GoF.

[An interesting experiment... Note that some material is dated, but it's a wiki. -- Ed.]

More C++ Idioms

C++ has indeed become too "expert friendly" -- Bjarne Stroustrup, The Problem with Programming, Technology Review, Nov 2006.

Stroustrup's saying is true because experts are intimately familiar with the idioms in the language. With the increase in the idioms a programmer understands, the language becomes friendlier to him or her. The objective of this open content book is to present modern C++ idioms to programmers who have moderate level of familiarity with C++, and help elevate their knowledge so that C++ feels much friendlier to them. It is designed to be an exhaustive catalog of reusable idioms that expert C++ programmers often use while programming or designing using C++. This is an effort to capture their techniques and vocabulary into a single work. This book describes the idioms in a regular format: Name-Intent-Motivation-Solution-References, which is succinct and helps speed learning. By their nature, idioms tend to have appeared in the C++ community and in published work many times. An effort has been made to refer to the original source(s) where possible; if you find a reference incomplete or incorrect, please feel free to suggest or make improvements.

The world is invited to catalog reusable pieces of C++ knowledge (similar to the book on design patterns by GoF). The goal here is to first build an exhaustive catalog of modern C++ idioms and later evolve it into an idiom language, just like a pattern language. Finally, the contents of this book can be redistributed under the terms of the GNU Free Documentation License.

Aimed toward: Anyone with an intermediate level of knowledge in C++ and supported language paradigms

 

Generating OpenCL/CUDA source code from C++ expressions in VexCL

A solution to generate code for CUDA and OpenCL with C++:

Generating OpenCL/CUDA source code from C++ expressions in VexCL

by Denis Demidov

From the talk description:

VexCL is an opensource C++ vector expression template library for OpenCL/CUDA. It has been created for ease of GPGPU development with C++ and provides convenient and intuitive notation for linear algebra operations, vector arithmetic and various parallel primitives.

Await, coroutines, what could that bring for game development

[This article is interesting not only because it's about work being proposed for consideration in the Concurrency TS, but also because it's interesting that we seem to be seeing a trend of articles being published on GitHub instead of on a blog... --Ed.]

 

Await, coroutines, what could that bring for game development

This article shows how we can use await in way not related to threading, tasks, or asynchronous I/O, but in the context of a game, to write game logic-related code spanning accross many frames in a sequencial way, without introducing any threads with little to no performance penalty.

Ask the STL Creator about Generic Programming

An online (Slashdot) interview of Alexander Stepanov and Daniel Rose, authors of "From Mathematics to Generic Programming" is now soliciting questions.

Add a reply to this Slashdot announcement to pose a questions. Ask as many questions as you'd like, but only one question per reply please:

Interview: Ask Alexander Stepanov and Daniel E. Rose a Question

An anonymous reader writes:

"Alexander Stepanov studied mathematics at Moscow State University and has been programming since 1972. His work on foundations of programming has been supported by GE, Brooklyn Polytechnic, AT&T, HP, SGI, and, since 2002, Adobe. In 1995 he received the Dr. Dobb's Journal Excellence in Programming Award for the design of the C++ Standard Template Library. Currently, he is the Senior Principal Engineer at A9.com. Daniel E. Roseis a programmer and research scientist who has held management positions at Apple, AltaVista, Xigo, Yahoo, and is the Chief Scientist for Search at A9.com. His research focuses on all aspects of search technology, ranging from low-level algorithms for index compression to human-computer interaction issues in web search. Rose led the team at Apple that created desktop search for the Macintosh. In addition to working together, the pair have recently written a book, From Mathematics to Generic Programming. Alexander and Daniel have agreed to answer any questions you may have about their book, their work, or programming in general. As usual, ask as many as you'd like, but please, one per post."

Multiplatform C++ - Edouard Alligand @ Meeting C++ 2014

The latest version of Edouard Alligands talk on Multiplatform development with C++:

Multiplattform C++

by Edouard Alligand

From the talk description:

C++ is a multiplatform language, yet many difficulties arise when you want the same code to compile properly and function identically on different platforms. If you put aside the obvious system programming related obstacles, and the differences you might have between compilers (especially when it comes to supporting C++11 and C++14), you come to the surprising conclusion that what is truly hard is all the “little things” you didn’t anticipate.

Quick Q: Why does trying to use a std::move'd object try to copy? -- StackOverflow

Quick A: Think of move is (mostly) an optimization of copy, and copy as the "slow" fallback when you can't actually move.

Fresh on SO:

Why does calling std::move on a const object call the copy constructor when passed to another object?

Specifically, the code

#include <iostream>

struct Foo {
    Foo() = default;
    Foo(Foo && x) { std::cout << "Move" << std::endl; }
    Foo(Foo const & x) = delete;
};

int main() {
    Foo const x; Foo y(std::move(x));
}

fails to compile with the message:

g++ -std=c++14 test07.cpp -o test07
test07.cpp: In function 'int main()':
test07.cpp:10:36: error: use of deleted function 'Foo::Foo(const Foo&)'
     Foo const x; Foo y(std::move(x));
                                    ^
test07.cpp:6:5: note: declared here
     Foo(Foo const & x) = delete;
     ^
Makefile:2: recipe for target 'all' failed
make: *** [all] Error 1

Certainly, I expect it to fail because we can't move a const value. At the same time, I don't understand the route that the code takes before it tries to call the copy constructor. Meaning, I know that std::move converts the element to an x-value, but I don't know how things proceed after that with respect to const.

Targeting Android with the C++ REST SDK -- Steven Gates

Fresh on vcblog:

Targeting Android with the C++ REST SDK

by Steven Gates

From the article:

Right before the holidays we put together a new release, version 2.4.0, of the C++ REST SDK. One of the new features added in the library is support for targeting Android using the Visual Studio 2015 cross platform mobile development, as well as the x86 Android emulator. In this post I’m going to walk through showing how to create an Android Native Activity that utilizes the C++ REST SDK...

C++ Status at the end of 2014 -- Bartlomiej Filipek

A turn-of-the-year retrospective:

C++ Status at the end of 2014

by Bartlomiej Filipek

From the article:

This was a good year for C++!

Short summary (language features):

  • Clang supports C++14
  • GCC supports C++11 and most of C++14 (Full support in upcoming GCC 5.0)
  • Intel 15.0 supports C++11 (some features on Linux/OSX only)
  • Visual Studio tries to catch up with C++11, but it also introduces C++14 features as well... and it become (almost) free!

JSON for Modern C++ -- Niels Lohmann

A new GitHub project With a very readable README:

JSON for Modern C++

by Niels Lohmann

From the README:

... You can create an object (deserialization) by appending _json to a string literal:

// create object from string literal
json j = "{ \"pi\": 3.141, \"happy\": true }"_json;

[Note: Or perhaps auto j = R"({ "pi": 3.141, "happy": true })"_json; --Ed.]

You can also get a string representation (serialize):

// explicit conversion to string
std::string s = j.to_string();