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Moving to c++11

c++11 has been officially released since August 2011. I'm not sure if other compilers are planning or have added c++11 support but I primarily use gcc. Even though gcc still classifies c++11 support as experimental their support appears nearly complete.

At my day job we've been doing some prototyping and early development of a next generation platform and have started to try out c++11. So far I've been happy with the improvements in c++11 over c++98. After a handful of months of using c++11 here are the things that have stood out.

auto
The 'auto' keyword mirrors one of my favorite language features in c#, the 'var' keyword. auto indicates that the compiler should perform type-inference. With auto I'm not going to miss having to type dozen of letters twice to declare and create a verbosely named template. Two pitfalls of auto are the lack of a specific type that might require a programmer to look at the function prototype to determine the type of a variable, and getting types you didn't expect when using std library iterators. Languages like c#, javascript and python have been getting along with equivalents to auto so it seems like c++ can too.

Threading support
C++11 integrates threading support. This means you can write a multi-threaded application without having to use os specific thread functions. Usually we end up using compiler or platform conditionals to encapsulate posix pthreads or Windows threading calls, or abstracting these into a class. All of that falls away with c++11 threading support. Now, if you have c++11 support on your target platforms, you can ditch the OS specific thread code.

Condition variables
We've been replacing some OS specific event wait code with c++11's condition variable support. A lot of our code involves services that communicate with hardware. These services tend to receive data and place it on queues for other threads to process. Having condition variables built into the language has enabled us to transition away from various pthread mutex and condition functions to something that functions the same but has the possibility of working on Windows or other OSes.

Lambdas
So far we've primarily used lambda expressions to add logic checks to condition variables without having to create separate named functions. I think we will expand our use of lambdas as we build more code that takes advantage of std containers.


I might be arriving a little late to the c++11 party having only started using it a handful of months ago. The language improvements are making c++ much smoother to develop with. I've been enjoying similar features in c# for several years now and encouraging fellow developers to consider c#, python and javascript because they seem more productive to develop in. Since using c++11 I've been encouraging these same developers to take advantage of c++11 features if they are going to be developing in c++. C++ still doesn't feel as productive as c#, python or javascript does but c++11 goes a long way to smoothing over a lot of the rough edges. It almost feels like a new language.

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