C++ Software Design

Chapter 2. The Art of Building Abstractions

Abstractions play a vital role in software design and software architecture. In other words, good abstractions are the key to managing complexity. Without them, good design and proper architecture are hard to imagine. Still, building good abstractions and using them well is surprisingly difficult. As it turns out, building and using abstractions comes with a lot of subtleties, and therefore feels more like an art than a science. This chapter goes into detail about the meaning of abstractions and the art of building them.

In “Guideline 6: Adhere to the Expected Behavior of Abstractions”, we will talk about the purpose of abstractions. We will also talk about the fact that abstractions represent a set of requirements and expectations and why it is so important to adhere to the expected behavior of abstractions. In that context I will introduce another design principle, the Liskov Substitution Principle (LSP).

In “Guideline 7: Understand the Similarities Between Base Classes and Concepts”, we will compare the two most commonly used abstractions: base classes and concepts. You will understand that from a semantic point of view both approaches are very similar since both are able to express expected behavior.

In “Guideline 8: Understand the Semantic Requirements of Overload Sets”, I will extend the discussion about semantic requirements and talk about a third kind of abstraction: function overloading. You will understand that all functions, ...