Book Image

Hands-On Design Patterns with C++ (Second Edition) - Second Edition

By : Fedor G. Pikus
5 (1)
Book Image

Hands-On Design Patterns with C++ (Second Edition) - Second Edition

5 (1)
By: Fedor G. Pikus

Overview of this book

C++ is a general-purpose programming language designed for efficiency, performance, and flexibility. Design patterns are commonly accepted solutions to well-recognized design problems. In essence, they are a library of reusable components, only for software architecture, and not for a concrete implementation. This book helps you focus on the design patterns that naturally adapt to your needs, and on the patterns that uniquely benefit from the features of C++. Armed with the knowledge of these patterns, you’ll spend less time searching for solutions to common problems and tackle challenges with the solutions developed from experience. You’ll also explore that design patterns are a concise and efficient way to communicate, as patterns are a familiar and recognizable solution to a specific problem and can convey a considerable amount of information with a single line of code. By the end of this book, you’ll have a deep understanding of how to use design patterns to write maintainable, robust, and reusable software.
Table of Contents (26 chapters)
1
Part 1: Getting Started with C++ Features and Concepts
5
Part 2: Common C++ Idioms
10
Part 3: C++ Design Patterns
18
Part 4: Advanced C++ Design Patterns

Type substitution in template functions

We must carefully differentiate between the two steps in instantiating a template function to match a particular call - first, the types of the template parameters are deduced from the argument types (a process referred to as type deduction). Once the types are deduced, the concrete types are substituted for all parameter types (this is a process called type substitution). The difference becomes more obvious when the function has multiple parameters.

Type deduction and substitution

Type deduction and substitution are closely related, but not exactly the same. The deduction is the process of “guessing:” what should the template type, or types, be in order to match the call? Of course, the compiler does not really guess but applies a set of rules defined in the standard. Consider the following example:

// Example 07
template <typename T>
void f(T i, T* p) { std::cout << “f(T, T*)” << std::endl...