advanced

"Panel: Static If, C++11, Modern Libraries, and Metaprogramming" -- Alexandrescu, Meyers, Sutter

The first panel from C++ and Beyond 2012 is now available on Channel 9:

On Static If, C++11 in 2012, Modern Libraries, and Metaprogramming

Andrei Alexandrescu, Scott Meyers, Herb Sutter

Channel 9 was invited to this year's C++ and Beyond to film some sessions (that will appear on C9 over the coming months!)...

At the end of day 2, Andrei, Herb and Scott graciously agreed to spend some time discussing various modern C++ topics and, even better, answering questions from the community. In fact, the questions from Niners (and a conversation on reddit/r/cpp) drove the conversation.

Here's what happened...

[more]

User-Defined Literals, Part 1 -- Andrzej KrzemieĊ„ski

New article by Andrzej Krzemieński:

User-defined literals — Part I

This post is about the new language feature: the ability to specify user-defined literals. You may already be familiar with it, for example from N2750. In this post we will talk about literals in general, the purpose and usefulness of user-defined literals, their limitations, and alternatives in C++ to achieve similar goals.

[more]

Destructors That Throw: Evil, or Just Misunderstood? -- Jon Kalb and Dave Abrahams

Interesting new C++Next article about destructors that throw:

Evil, or Just Misunderstood?

by Jon Kalb and Dave Abrahams

From the script-style intro:

UDT (putting down drink and looking deep into CODER’s eyes): By the way, in my destructor I throw if the file fails to close properly.

CODER: I can live with that. [...] I’ve always been a sucker for dangerous types.

FADE TO BLACK

NARRATOR (V.O.): We invite you to journey with us now, into the heart of darkness, where we seek out throwing destructors and stare Evil™ in the face. Will CODER survive his encounter with exceptional destruction? The answers lie beyond the frontiers of usual best practice…

Continue reading...

Core C++, 3 of N: Overload Resolution -- Stephan T. Lavavej

Core C++, 3 of N: Overload Resolution -- Stephan T. Lavavej

Stephan T. Lavavej, aka STL, will take us on a journey of discovery within the exciting world of Core C++. We know lots of folks are either coming back to C++, coming to C++, or have never left C++. This lecture series, in n parts, is for all of you! Only STL can make that work (novice, intermediate, and advanced all bundled together and presented in a way only STL can do).

In Part 3, STL digs into Overload Resolution. A function template can overload non-template functions of the same name. In this scenario, function calls are resolved by first using template argument deduction to instantiate the function template with a unique specialization (STL taught us all about TAD in Part 2). If template argument deduction fails, the other function overloads are considered to resolve the call. These other overloads, also known as the candidate set, include nontemplate functions and other instantiated function templates. If template argument deduction succeeds, then the generated function is compared with the other functions to determine the best match, following the rules for overload resolution. [source]

As STL says: "I walk through why foo(const T&) beats foo(const T *), when given int *. The reason is surprisingly subtle."

Tune in.

Core C++, 2 of N: Template Argument Deduction -- Stephan T. Lavavej

Core C++, 2 of N: Template Argument Deduction -- Stephan T. Lavavej

Stephan T. Lavavej, aka STL, will take us on a journey of discovery within the exciting world of Core C++. We know lots of folks are either coming back to C++, coming to C++, or have never left C++. This lecture series, in n parts, is for all of you! Only STL can make that work (novice, intermediate, and advanced all bundled together and presented in a way only STL can do).

In part 2, STL will teach us all about Template Argument Deduction. Template arguments are deduced when a call is made to a template function, but some or all template arguments are omitted. The compiler will attempt to deduce the intended template arguments. In most cases, this works as expected. If it does not, a compilation error occurs, in which case you should specify the template arguments explicitly. Now, let's see what Stephan has to say about this.

Tune in. Learn.

Core C++, 1 of N: Name Lookup -- Stephan T. Lavavej

Core C++, 1 of N: Name Lookup -- Stephan T. Lavavej

Stephan T. Lavavej, aka STL, will take us on a journey of discovery within the exciting world of Core C++. We know lots of folks are either coming back to C++, coming to C++, or have never left C++. This lecture series, in n parts, is for all of you! Only STL can make that work (novice, intermediate, and advanced all bundled together and presented in a way only STL can do).

In the following code, which functions are called? Why? Analyze the implications?

 

namespace A {
      struct X;
      struct Y;
      void f( int );
      void g( X );
}

namespace B {
       void f( int i ) {
            f( i );   // which f()?
        }
        void g( A::X x ) {
             g( x );   // which g()?
        }
        void h( A::Y y ) {
             h( y );   // which h()?
        }
}


We recommend you watch this entire episode before playing around with Herb's sample above (and don't read the GotW answer, either! That's cheating. Learn from STL. He's an outstanding teacher, as you know).

Tune in. Enjoy. Learn.