Book Image

Template Metaprogramming with C++

By : Marius Bancila
5 (1)
Book Image

Template Metaprogramming with C++

5 (1)
By: Marius Bancila

Overview of this book

Learn how the metaprogramming technique enables you to create data structures and functions that allow computation to happen at compile time. With this book, you'll realize how templates help you avoid writing duplicate code and are key to creating generic libraries, such as the standard library or Boost, that can be used in a multitude of programs. The introductory chapters of this book will give you insights into the fundamentals of templates and metaprogramming. You'll then move on to practice writing complex templates and exploring advanced concepts such as template recursion, template argument deduction, forwarding references, type traits, and conditional compilation. Along the way, you'll learn how to write variadic templates and how to provide requirements to the template arguments with C++20 constraints and concepts. Finally, you'll apply your knowledge of C++ metaprogramming templates to implement various metaprogramming patterns and techniques. By the end of this book, you'll have learned how to write effective templates and implement metaprogramming in your everyday programming journey.
Table of Contents (16 chapters)
Part 1: Core Template Concepts
Part 2: Advanced Template Features
Part 3: Applied Templates
Appendix: Closing Notes

Chapter 2, Template Fundamentals

Question 1

What category of types can be used for non-type template parameters?


Non-type template parameters can only have structural types. Structure types are integral types, floating-point types (as of C++20), enumeration types, pointer types (either to objects or functions), pointer to member types (either to member objects or member functions), lvalue reference types (either to objects or functions), and literal class types that meet several requirements: all base classes are public and non-mutable, all non-static data members are public and non-mutable, and the types of all the base classes and the non-static data members are also structural types or arrays thereof. const and volatile qualified versions of these types are also allowed.

Question 2

Where are default template arguments not allowed?


Default template arguments cannot be used for parameter packs, in declarations of friend class templates, and in the...