Book Image

Hands-On Design Patterns with C++

By : Fedor G. Pikus
Book Image

Hands-On Design Patterns with C++

By: Fedor G. Pikus

Overview of this book

C++ is a general-purpose programming language designed with the goals of efficiency, performance, and flexibility in mind. 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. The focus of this book is on the design patterns that naturally lend themselves to the needs of a C++ programmer, and on the patterns that uniquely benefit from the features of C++, in particular, the generic programming. Armed with the knowledge of these patterns, you will spend less time searching for a solution to a common problem and be familiar with the solutions developed from experience, as well as their advantages and drawbacks. The other use of design patterns is as a concise and an efficient way to communicate. A pattern is a familiar and instantly recognizable solution to specific problem; through its use, sometimes with a single line of code, we can convey a considerable amount of information. The code conveys: "This is the problem we are facing, these are additional considerations that are most important in our case; hence, the following well-known solution was chosen." By the end of this book, you will have gained a comprehensive understanding of design patterns to create robust, reusable, and maintainable code.
Table of Contents (21 chapters)

Chapter 4

  • What does swap do?

The swap function exchanges the state of the two objects. After the swap call, the objects should remain unchanged, except for the names they are accessed by.

  • How is swap used in exception-safe programs?

Swap is usually employed in programs that provide commit-or-rollback semantics; a temporary copy of the result is created first, then swapped into its final destination only if no errors were detected.

  • Why should the swap function be non-throwing?

The use of swap to provide commit-or-rollback semantics assumes that the swap operation itself cannot throw an exception or otherwise fail and leave the swapped objects in an undefined state.

  • Should a member or a non-member implementation of swap be preferred?

A non-member swap function should always be provided, to ensure that the calls to non-member swap are executed correctly. A member swap function...