Professional C++

Chapter 4. Designing with Libraries and Patterns

Experienced C++ programmers never start a project from scratch. They incorporate code from a wide variety of sources, such as the standard template library, open-source libraries, proprietary code bases in their workplace, and their own code from previous projects. In addition, good C++ programmers reuse approaches or strategies to address various common design issues. These strategies can range from a technique that worked for a past project to a formal design pattern. This chapter explains how to take into account existing code and strategies when designing your programs.

Chapter 2 introduced the theme of reuse, explaining that it can apply both to code reuse and to idea reuse. This chapter expands on that theme by giving specific details and strategies that you can use in your program designs. After finishing this chapter, you will understand:

• The different types of code available for reuse

• The advantages and disadvantages of code reuse

• General strategies and guidelines for reusing code

• Open-source libraries

• The C++ standard library

• Design techniques and patterns

Reusing Code

You should reuse code liberally in your designs. In order to make the most of this rule, you need to understand the types of code that you can reuse and the tradeoffs involved in code reuse.

A Note on Terminology

Before analyzing the advantages and disadvantages of code reuse, it is helpful to specify the terminology involved and to categorize the types of reused code. ...