This book guides you through the evolution of C++ Lambda Expressions so that you can learn it step by step. We'll start with C++03 and a motivation to have "ad-hoc" functors, and then we'll move into the latest C++ standards:

• C++11 - early days of the feature. You'll learn about all the essential aspects of lambdas and several tricks you might apply. This is the longest chapter as we need to cover a lot of topics.
• C++14 - updates. See how to use generic lambdas and captures with an initialiser.
• C++17 - more improvements, especially by handling `this` pointer and allowing `constexpr`. You'll also learn about the overloaded pattern and how to derive from lambda.
• C++20 - in this section you'll see all of the new features adopted for C++20 like template lambdas and how to use them with concepts and constexpr algorithms.

Additionally, throughout the chapters, you'll learn about the following techniques:

• Immediately Invoked Functional Expressions (IIFE)
• How to instrument a default functor to gather extra information
• Replacing std::bind1st, std::bind2nd and removed functional stuff
• The Overloaded Pattern and how to inherit from a lambda
• Passing C++ captureless lambda as a function pointer to C API
• LIFTING with lambdas
• Storing lambdas in a container
• Variadic templates and arguments packs
• Lambdas and asynchronous execution
• and many more

While the book is 100% ready, I might release some "hot-fixes" smaller releases. All existing readers get new updates for free.

The book is inspired by two articles that appeared at cppstories.com:

• Lambdas: From C++11 to C++20, Part 1
• Lambdas: From C++11 to C++20, Part 2

The articles also are based on a live coding presentation given by C++ Expert Tomasz Kamiński at our local Cracow C++ User Group.

Readers Feedback & Reviews

Below, you can find the GoodReads page for the book with the readers' feedback:

C++ Lambda Story @GoodReads

And a review at Adam Sawicki Blog:

Book Review: C++ Lambda Story

FAQ

I'm a beginner in C++? Is that book for me?

The book assumes that you have a basic knowledge of C++. I suggest taking some elementary course first.

I'm an expert, and I know everything about C++? Is that book for me?

Yeah... you know all about C++? Is this possible? :)

Anyway, in your case, the book will give you a good refresher and even will show you some new tricks.

I'm not a beginner nor an expert...?

Perfect! So the book will show you lots of examples that will expand your knowledge and also remind you things that you may already know.

Additionally, throughout the book, you'll see other techniques and features related to modern C++ like, `constexpr`, exceptions, fold expressions, `std::thread`, perfect forwarding using callable objects and many more.

Is this a historical book with lots of boring descriptions?

The flow of the book focuses on the background behind lambda expression and its evolution. But it's meant to teach you practical things. You'll learn the lambdas step by step, understanding new capabilities that lambdas got with each C++ revision.

Will I get free updates?

Yes! While the book is 100% ready, I might add some more updates in the future, mainly bug fixes.

That's why it's best to buy the book as early as possible; for example, the earliest version of the book was completely free.

The content looks like copied directly from the blog, so what's the point to buy it?

The very early version of the book was adapted directly from the blog... but then most of the content was rewritten and heavily updated. Now, you get at least 4x of what's available on the blog, not to mention the better quality and a nice-looking pdf/ebook (there's no need to click and jump between separate blog articles).

On the Internet there's lots of free content about lambdas, so why buy the book?

Sure! Even on my blog, you can find lots of articles about lambda expression. The C++ draft is also free, so you can read the specification on your own. Or have an additional explanation from great cppreference pages.

But the book will save you lots of your precious time looking for those quality content, extra examples, extended descriptions. What's more, by having a nice learning flow, you can understand this powerful C++ feature much faster at a super low price.

Is there a refund option?

Yes! if you buy the Book through Leanpub, then you have a 45-day guarantee. (Not applicable with Kindle direct Publishing though).

You can also download a preview with almost 60 pages.

Did I miss something?

If you have more questions, then please ask directly and write at bartek AT cppstories.com.

Initialization in C++ is a hot topic! The internet is full of discussions about best practices, and there are even funny memes on that subject. The situation is not surprising, as there are more than a dozen ways to initialize a simple integer value, complex rules for the auto-type deduction, data members, and object lifetime nuances.

And here comes the book.

Throughout this text, you will learn practical options to initialize various categories of variables and data members in Modern C++. More specifically, this text teaches multiple types of initialization, constructors, non-static data member initialization, inline variables, designated initializers, and more. Additionally, you’ll see the changes and new techniques from C++11 to C++20 and lots of examples to round out your understanding.

The plan is to explain most (if not all) parts of initialization, learn lots of excellent C++ techniques, and see what happens under the hood.

The goal of this book is to equip you with the following knowledge:

• Explain rules about object initialization, including regular variables, data members, and non-local objects.
• How to implement special member functions (constructors, destructors, copy/move operations) and when they are helpful.
• How to efficiently initialize non-static data members using C++11 features like non-static data member initialization, inheriting, and delegating constructors.
• How to streamline working with static variables and static data members with inline variables from C++17.
• How to work with container-like members, non-copyable data members (like `const` data members) or move-able only data members, or even lambdas.
• What is an aggregate, and how to create such objects with designated initializers from C++20.

The book contains 14 chapters in the following structure:

• Chapters 1 to 5 create a foundation for the rest of the book. They cover basic initialization rules, constructors, destructors, and the basics of data members.
• Chapter 6 is a short quiz on constructors. You can check your knowledge from the first "part" of the book.
• Chapter 7 (in progress): Type deduction.
• Chapter 8 describes Non-static Data Member Initialization (NSDMI), a powerful feature from C++11 that improves how we work with data members. At the end of the chapter, you can solve a few exercises.
• Chapter 9 discusses how to initialize container-like data members.
• Chapter 10 contains information about non-regular data members and how to handle them in a class. You'll learn about `const` data members, `unique_ptr` as a data member, and references.
• Chapter 11 describes static non-local variables, static objects, various storage duration options, `inline` variables from C++17 and `constinit` from C++20.
• * Chapter 12 moves to C++20 and describes Designated Initializers, a handy feature based on similar thing from the C language.
• * Chapter 13 shows various techniques like passing strings into constructors, strong typing, CRTP class counter, Copy and swap idiom, and more.
• Chapter 14 is the final quiz with questions from the whole book.

And there are two appendices:

• Appendix A - a handy guide about rules for compiler-generated special member functions.
• Appendix B - answers to quizzes and exercises.

Most sections are completed, but I'm still working on filling two chapters and polishing the quality.

Who is this book for?

The book is intended for beginner/intermediate C++ programmers who want to learn how to work with static and non-static class data members in Modern C++ (from C++11 to C++20).

You should know at least some of the basics of creating and using custom classes.

This text is also helpful for experienced programmers who know older C++ standards and want to move into C++17/C++20