Book Image

Boost C++ Application Development Cookbook - Second Edition

By : Anton Polukhin Alekseevic
Book Image

Boost C++ Application Development Cookbook - Second Edition

By: Anton Polukhin Alekseevic

Overview of this book

If you want to take advantage of the real power of Boost and C++ and avoid the confusion about which library to use in which situation, then this book is for you. Beginning with the basics of Boost C++, you will move on to learn how the Boost libraries simplify application development. You will learn to convert data such as string to numbers, numbers to string, numbers to numbers and more. Managing resources will become a piece of cake. You’ll see what kind of work can be done at compile time and what Boost containers can do. You will learn everything for the development of high quality fast and portable applications. Write a program once and then you can use it on Linux, Windows, MacOS, Android operating systems. From manipulating images to graphs, directories, timers, files, networking – everyone will find an interesting topic. Be sure that knowledge from this book won’t get outdated, as more and more Boost libraries become part of the C++ Standard.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Detecting int128 support


Some compilers have support for extended arithmetic types such as 128-bit floats or integers. Let's take a quick glance at how to use them using Boost.

We'll be creating a method that accepts three parameters and returns the multiplied value of those methods. If compiler supports 128-bit integers, then we use them. If compiler supports long long, then we use it; otherwise, we need to issue a compile-time error.

Getting ready

Only the basic knowledge of C++ is required.

How to do it...

What do we need to work with 128-bit integers? Macros that show that they are available and a few typedefs to have portable type names across platforms.

  1. Include a header:
#include <boost/config.hpp>
  1. Now, we need to detect int128 support:
#ifdef BOOST_HAS_INT128
  1. Add some typedefs and implement the method as follows:
typedef boost::int128_type int_t;
typedef boost::uint128_type uint_t;

inline int_t mul(int_t v1, int_t v2, int_t v3) {
    return v1 * v2 * v3;
}
  1. For compilers that do not support...