Book Image

C++ Fundamentals

By : Antonio Mallia, Francesco Zoffoli
Book Image

C++ Fundamentals

By: Antonio Mallia, Francesco Zoffoli

Overview of this book

C++ Fundamentals begins by introducing you to the C++ compilation model and syntax. You will then study data types, variable declaration, scope, and control flow statements. With the help of this book, you'll be able to compile fully working C++ code and understand how variables, references, and pointers can be used to manipulate the state of the program. Next, you will explore functions and classes — the features that C++ offers to organize a program — and use them to solve more complex problems. You will also understand common pitfalls and modern best practices, especially the ones that diverge from the C++98 guidelines. As you advance through the chapters, you'll study the advantages of generic programming and write your own templates to make generic algorithms that work with any type. This C++ book will guide you in fully exploiting standard containers and algorithms, understanding how to pick the appropriate one for each problem. By the end of this book, you will not only be able to write efficient code but also be equipped to improve the readability, performance, and maintainability of your programs.
Table of Contents (9 chapters)
C++ Fundamentals

Introducing Functors

A Functor (function object) is similar to a class. The class that overloads the operator() function is also known as the function call operator.

The syntax that's used to define a functor is as follows:

class class_name {
    type operator()(type arg) {} 

The function call operator has a return type and takes any number of arguments of any type. To invoke the call operator of an object, we can write the name of the object, followed by parentheses containing the arguments to pass to the operator. You can imagine that an object that provides a call operator can be used in the same way as you would use a function. Here's an example of a functor:

class_name obj;
type t;
/* obj is an instance of a class with the call operator: it can be used as if it was a function */

They are particularly useful in places where you can pass a function object to an algorithmic template that accepts an object with operator() defined. This exploits code reusability and testability...