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

Understanding the constrained algorithms

The standard library provides over one hundred general-purpose algorithms. As we discussed in the introductory section for the ranges library earlier, these have one thing in common: they work with abstract ranges with the help of iterators. They take iterators as arguments and they sometimes return iterators. That makes it cumbersome to repeatedly use with standard containers or arrays. Here is an example:

auto l_odd = [](int const n) {return n % 2 == 1; };
std::vector<int> v{ 1, 1, 2, 3, 5, 8, 13 };
std::vector<int> o;
auto e1 = std::copy_if(v.begin(), v.end(),
int arr[] = { 1, 1, 2, 3, 5, 8, 13 };
auto e2 = std::copy_if(std...