Book Image

C++17 STL Cookbook

By : Jacek Galowicz
Book Image

C++17 STL Cookbook

By: Jacek Galowicz

Overview of this book

C++ has come a long way and is in use in every area of the industry. Fast, efficient, and flexible, it is used to solve many problems. The upcoming version of C++ will see programmers change the way they code. If you want to grasp the practical usefulness of the C++17 STL in order to write smarter, fully portable code, then this book is for you. Beginning with new language features, this book will help you understand the language’s mechanics and library features, and offers insight into how they work. Unlike other books, ours takes an implementation-specific, problem-solution approach that will help you quickly overcome hurdles. You will learn the core STL concepts, such as containers, algorithms, utility classes, lambda expressions, iterators, and more, while working on practical real-world recipes. These recipes will help you get the most from the STL and show you how to program in a better way. By the end of the book, you will be up to date with the latest C++17 features and save time and effort while solving tasks elegantly using the STL.
Table of Contents (18 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Transforming the contents of containers


If std::copy is the simplest STL algorithm for application on ranges, std::transform is the second simplest STL algorithm. Just as copy, it copies items from one range to another but additionally accepts a transformation function. This transformation function can alter the value of the input type before it is assigned to an item in the destination range. Furthermore, it can even construct a completely different type, which is useful if the source range and destination range differ in their payload item types. It is simple to use but still very useful, which makes it an ordinary standard component used in portable day-to-day programs.

How to do it...

In this section, we are going to use std::transform in order to modify the items of a vector while copying them:

  1. As always, we first need to include all the necessary headers and to spare us some typing, we declare that we use the std namespace:
       #include <iostream>
       #include <vector&gt...