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

Chapter 4, Swap - From Simple to Subtle

  1. 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.
  2. 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.
  3. 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.
  4. 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 can also be provided, for two reasons—first, it is the only way to swap an object with a temporary, and second, the swap implementation usually needs access to the private data members of the class. If both are provided, the non-member...