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

Sharing different member values of the same object


Let's imagine we are maintaining a shared pointer to some complex, composed, and dynamically allocated object. Then, we want to start a new thread that does some time-consuming work on a member of this complex object. If we want to release this shared pointer now, the object will be deleted while the other thread is still accessing it. If we don't want to give the thread object the pointer to the whole complex object because that would mess with our nice interface, or for other reasons, does this mean that we have to do manual memory management now?

No. It is possible to use shared pointers that on one hand, point to a member of a large shared object, while on the other hand, perform automatic memory management for the entire initial object.

In this example, we will create such a scenario (without threads to keep it simple) in order to get a feeling for this handy feature of shared_ptr.

How to do it...

We are going to define a structure that...