Book Image

Modern C++ Programming Cookbook

By : Marius Bancila
Book Image

Modern C++ Programming Cookbook

By: Marius Bancila

Overview of this book

C++ is one of the most widely used programming languages. Fast, efficient, and flexible, it is used to solve many problems. The latest versions of C++ have seen programmers change the way they code, giving up on the old-fashioned C-style programming and adopting modern C++ instead. Beginning with the modern language features, each recipe addresses a specific problem, with a discussion that explains the solution and offers insight into how it works. You will learn major concepts about the core programming language as well as common tasks faced while building a wide variety of software. You will learn about concepts such as concurrency, performance, meta-programming, lambda expressions, regular expressions, testing, and many more in the form of recipes. These recipes will ensure you can make your applications robust and fast. By the end of the book, you will understand the newer aspects of C++11/14/17 and will be able to overcome tasks that are time-consuming or would break your stride while developing.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Implementing parallel map and fold with tasks


Tasks are a higher-level alternative to threads for performing concurrent computations. std::async() enables us to execute functions asynchronously, without the need to handle lower-level threading details. In this recipe, we will take the same task of implementing a parallel version of the map and fold functions, as in the previous recipe, but we will use tasks and see how it compares with the thread version.

Getting ready

The solution presented in this recipe is similar in many aspects to the one that uses threads in the previous recipe, Implementing parallel map and fold with threads. Make sure you read that one before continuing with the current recipe.

How to do it...

To implement a parallel version of the map function, do the following:

  1. Define a function template that takes a begin and end iterator to a range, and a function to apply to all the elements:
        template <typename Iter, typename F>
        void parallel_map(Iter begin,...