November 2014

C++ User Group Meetings in December

Its again the time to list the monthly meetings, this time its for December:

C++ User Group Meetings in December

by Jens Weller

From the Article

Three years ago, my own user group had its first meeting in December, being the second active C++ user group in Europe back in 2011. Since then a lot has changed, this December there are a lot more user groups meeting, and also we'll have the last premier C++ Event of the year: Meeting C++ is next week!

Meetings in December

    1.12 C++ UG Hungary - Template Metaprogramming With Better Tools
    2.12 C++ UG Chicago - The Bash Bug And The OpenSSL Bug
    3.12 C++ UG Saint Louis - Next meeting
    3.12 C++ UG Austin - Double Feature
    4.12 C++ UG Dublin - std::begin
    9.12 C++ UG San Francisco/ Bay area - C++11's New Pointer Types
    10.12 C++ UG Utah - Iterators\, Containers and Algorithms in the Standard Library
    10.12 C++ UG San Francisco/ Bay area - Presentation and Q&A
    11.12 C++ UG Dresden - Dezember Treffen
    13.12 C++ UG Pune, India - Introduction to C++ Template Metaprogramming and Domain Specific
    15.12 C++ UG Denver - Denver Tech Center C++ Developers
    15.12 C++ UG Austin - North Austin Monthly C/C++ Pub Social
    17.12 C++ UG Düsseldorf - Christmas special!
    18.12 C++ UG Paris - C++ FRUG #5 - L'asynchronisme en deux talks
    18.12 C++ UG Amsterdam - Let's have a meetup in December
    18.12 C++ UG Hamburg - Qt DevDays & Meeting C++

ODE simulations with Boost.odeint and Boost.SIMD

A very nice article on how to use boost::odeint and SIMD:

Boosting ODE simulations with Boost.odeint and Boost.SIMD

by Mario Mulansky

From the article:

Ordinary Differential Equations appear in numerous applications and finding their solution is a fundamental problem in science and engineering. Often one has to rely on numerical methods to approximate such solutions as in the presence of nonlinearities, no analytic solution can be found. Being such a frequent problem...

Design Patterns Revisited -- Bob Nystrom

Walk through (with practical examples) a handful of the original patterns the Gang of Four documented in C++.

Design Patterns Revisited

Design Patterns: Elements of Reusable Object-Oriented Software is nearly twenty years old by my watch. Unless you’re looking over my shoulder, there’s a good chance Design Patterns will be old enough to drink by the time you read this. For an industry as quickly moving as software, that’s practically ancient. The enduring popularity of the book says something about how timeless design is compared to many frameworks and methodologies.

While I think Design Patterns is still relevant, we’ve learned a lot in the past couple of decades. In this section, we’ll walk through a handful of the original patterns the Gang of Four documented. For each pattern, I hope to have something useful or interesting to say.

I think some patterns are overused (Singleton), while others are underappreciated (Command). A couple are in here because I want to explore their relevance specifically to games (Flyweight and Observer). Finally, sometimes I just think it’s fun to see how patterns are enmeshed in the larger field of programming (Prototype and State).

Quick Q: Does std::vector resize automatically when inserting new elements?--StackOverflow

Quick A: Yes.

Recently on SO:

Do Vectors resize automatically?

I am very sorry that I am asking such a beginner question but I am finding contradictory information online. I would ask at University but it is out until February next year.

Do Vectors resize automatically? Or do you need to check the current size periodically and resize when you need more room. It looks to be resizing for me automatically but I'm not sure if that is a feature or the compiler waving a magic wand.

Poco C++ Library release version 1.4.7p1

POCO Development Release 1.4.7p1 Available

This release fixes a few issues in 1.4.7 and earlier releases. Most important, the Visual C++ project files for Visual C++ 2010 and later have optimization enabled in release builds. Previous builds had optimization disabled due to a bug in Visual Studio when upgrading 2008 project files with custom optimization settings.

There’s a new feature as well – HTTPClientSession now supports a global proxy setting, which will be used by all instances of HTTP(S)ClientSession, including HTTP(S)StreamOpener.

Detailed information is available in the CHANGELOG.

Anti-IF idioms in C++ -- Marco Arena

I'm showing interactive examples of "anti-IF" idioms in C++, inspired by C# snippets which Claudio Pattarello proposed at the Italian Agile Day 2014.

Anti-IF idioms in C++

by Marco Arena

From the article:

In this post I’d like to show you how to rewrite these idioms in C++, starting from a C# snippet. And the resulting code is pretty much identical. [...] I'm not saying "this is the best thing you can do in C++". [...] Sure, we have specific idioms in our favorite language but I think it’s lovely that we are able to reuse the same code from other languages with a little effort. And this is also appealing for other programmers who want to experience C++, maybe by starting coding idioms they know. ...

Metaprogramming with Modern C++: The Haskell Metaphor -- Manu Sánchez

If you are one of who have been following our post series about template metaprogramming with modern C++, at this time you should have become a C++ template Guru. At least thats what I expect wink.

You know about class templates, function templates, value parameters, type parameters, variadic templates… Your template metaprogramming toolbox is full of great things to play with. Thats good, but you want to start playing with your compiler, writting some cool metaprograms.

Metaprogramming with Modern C++: The Haskell Metaphor

by Manu Sánchez

From the article:

Template metaprogramming was used to improve perfomance on high-computing libraries too, with some clever code transformations done thanks to tmp. The best example of this is the blitz++ library, one of the first examples of a real use case of template metaprogramming.

Since C++11 the language has evolved to support some ways of metaprogramming as a common and useful thing. Metaprogramming became a first class citizen in C++, instead of the obscure, magical, and freaking way to abuse the compiler it was at the beginning...

A software design principle: Don’t make me use your design -- Diego Rodríguez-Losada

Developing code in C++ for robotics, I often faced the problem of communicating via serial port with a robot, a sensor or any other device. C and C++ are languages supposedly very close to hardware. Furthermore, they are the most common and oldest mainstream programming languages out there. So communicating over a serial port in a portable way should be straightforward.

A software design principle: Don’t make me use your design

by Diego Rodríguez-Losada

From the article:

I have seen the pattern described in the article a few times in C and C++ projects, but very rarely in other languages (at least those that I have used more as java and python) and I believe there is a reason, not directly related to software design for it: the lack of a widely used dependency manager. And no, OS package managers, installers and so, are not enough to solve this problem. Even if the authors of these libraries decide to decouple the functionality of the SerialPort basic wrapper in their design, there is little gain in it, users should still manually extract those files and integrate them in their projects, which doesn’t sound as reasonable engineering and will produce, for sure, maintenance problems and lack of updates. It is really unlikely that the authors will decide to create a separate project/library for the SerialPort, it is more effort not only to do it in the short term, but also to maintain and work with it in the mid and long terms. So developers just roll out their designs, and fill the functionality in it as required. I’ve done it so many times too...

“Effective Modern C++” from Scott Meyers Review -- CoderGears Team

Today on CoderGrears:

“Effective Modern C++” from Scott Meyers Review

by CoderGears Team

From the article:

This month a new book from Scott Meyers become available, it’s the last one of its Effective software development series (More Effective C++, Effective STL   and Effective C++ ) .

In this book Scott Meyers focus on the new C++11 and C++14 standrads, currently few books talk about them. In the other side many resources are available on the web discussing these new standards. Why I need to read this book?

Here’s our feedback...

The Python API and C++ -- Scott Prager

Some interspecies dating, appropriately on the "multi-paradigm" blog:

The Python API and C++

by Scott Prager

From the article:

Recently, for a job interview task, I was asked to write a Python module with a C or C++ implementation to solve an otherwise simple task. Obviously, I chose C++. While I had never used the Python API before, I found that the existing information on extending Python with C quite sufficient. What surprised me, however, is how little information existed for using C++. A few libraries exist, like Boost.Python, PyCXX, and some utilities that parse C++ to create Python bindings, but I didn't find much in the way of actual information without examining the sources of these libraries. ...

... I have started working on a little utility library ( for personal use... [The Python C API has] many restrictions and it certainly puts a cramp on C++'s style, but the moral of this store is that just because you need to work with a C API doesn't mean you can't use modern C++ techniques.