Lambdas

Partial Function Application is a technique in which a function binds a few of its arguments and returns a function taking fewer arguments. This technique is related to a technique used in functional languages called currying.

Lambdas in C++20 can be default-constructed and support copy-assignment when they have no state. Lambdas can be used in unevaluated contexts. Additionally, they detect when you implicitly copy the this pointer. This means a significant cause of undefined behavior with lambdas is gone.

Thanks to C++20, lambdas have become more powerful. From the various lambda improvements, template parameters for lambdas are my favorite ones.

My last post C++20: The Big Four started with an overview of concepts, ranges, coroutines, and modules. Of course, C++20 has more to offer. Today, let's continue my overview of the core language.

Honestly, many programmers in my classes have issues with the syntactic sugar of lambdas. Desugaring lambdas with C++ Insights helps quite often.

An interface is a contract between a user and an implementer and should, therefore, be written with great care. This also holds true if you pass an operation as an argument.

First, I have to apologize. Today, I wanted to continue my journey through the C++ Core Guidelines with arithmetic expressions. In my seminar this week, we had a long discussion about switch statements in C/C++ and how they become unmaintainable. Honestly, I'm not a fan of the switch statements, and I have to say: there is life after the switch statements.

I can not think about modern C++ without lambda expressions. So my wrong assumption was that there are many rules for lambda expressions. Wrong! There are fewer than ten rules. But as ever I learned something new.

My favorite example, the dispatch table, shows how nicely the features in modern C++ work together. A dispatch table is a table of pointers to functions. In my case, it is a table of handles for polymorphic function wrappers.