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 Be sure that knowledge from this book won’t get outdated, as more and more Boost libraries become part of the C++ Standard.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

Getting a type of expression in C++03


In the previous recipes, we saw some examples of boost::bind usage. It may be a useful tool in pre-C++11 word, but it is hard to store boost::bind result as a variable in C++03.

#include <functional> 
#include <boost/bind.hpp> 

const ??? var = boost::bind(std::plus<int>(), _1, _1);

In C++11, we can use auto keyword instead of ??? and that will work. Is there a way to do it in C++03?

Getting ready

A knowledge of the C++11 auto and decltype keywords may help you to understand this recipe.

How to do it...

We will need a Boost.Typeof library for getting a return type of expression:

#include <boost/typeof/typeof.hpp>

BOOST_AUTO(var, boost::bind(std::plus<int>(), _1, _1));

How it works...

It just creates a variable with the name var, and the value of the expression is passed as a second argument. The type of var is detected from the type of expression.

There's more...

An experienced C++ reader will note that there are more keywords in...