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 Be sure that knowledge from this book won’t get outdated, as more and more Boost libraries become part of the C++ Standard.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

Selecting an optimal operator for a template parameter


Imagine that we are working with classes from different vendors that implement different numbers of arithmetic operations and have constructors from integers. We do want to make a function that increments by any one class that is passed to it. Also, we want this function to be effective! Take a look at the following code:

template <class T> 
void inc(T& value) { 
    // TODO:
    // call ++value 
    // or call value ++ 
    // or value += T(1); 
    // or value = value + T(1); 
}

Getting ready

Some basic knowledge of the C++ templates, and the Boost.TypeTrait or standard library type traits is required.

How to do it...

All the selecting can be done at compile time. This can be achieved using the Boost.TypeTraits library, as shown in the following steps:

  1. Let's start by making correct functional objects:
namespace detail {
    struct pre_inc_functor {
    template <class T>
        void operator()(T& value) const {
     ...