Pretty comfortable with my c++ code now; I get classes, I get using templates and STL, smart pointers, and to an extent, exceptions. What I don't get is most of the new 2011 standard. Lambdas confuse me, in both their syntax and their purpose.
I've looked up articles trying to show practical uses for them, but they seem to go even further above my head than just the word 'lambda'. Rvalue / moving seems confusing just as well; decltype... gah. None of the new stuff makes much of any sense. The only thing I've understood so far is auto, and to a half-way extent: the new for loop style.
I've read through a third of C++ Primer 5th, and so far it's not really shed any new light to me. The frustration of these new features and my inability to grasp them has me concerned... How is it some clicked onto the new concepts rather fast? And where can I go to get to that point?
Other people grokked them fast because lambdas aren't new other languages already had these, lambdas in C# for example, they started as nameless delegates. I see lambdas as a delegate/callback function that you specify in the same line as where you pass them to a function that needs a callback. The lambdas in C++11 have a more function approach and I find them easier to read then their C# counterparts, its the capture that is hard.
A good use for a lambda is when you want to extend a std::find or std::find_if or std::sort, instead of passing it a functor or callback, you pass it a lambda that specifies what you want the predicate for the function to be. This keeps the code for the predicate and call of that predicate closer together than the functor or callback options.
RValue/Move semantics is something that was sorely missed and you had to program around this like reserving the size of your vector if you knew how big it was going to be to avoid an array copy. Move semantics will allow you to care a little less about copy performance if implemented correctly.
Decltype is a way in which we can access the type of an expression, this is useful in meta template programming and generic programming where you had to hack around these things before.
auto and the new intialiser lists are the most useful features added in C++11 because it allows you to write your code in an easier fashion and avoid a parsing problem.
class Foo
{
};
void Bar()
{
Foo foo(); //The compiler sees this as a function prototype not the instantiation of an instance of Foo
Foo foo {}; //This is now always seen as creating and instance of Foo
}
