C++ Core Guidelines Explained: Best Practices for Modern C++

Chapter 3

Interfaces

Cippi assembles components.

An interface is a contract between a service provider and a service user. Interfaces are, according to the C++ Core Guidelines, “probably the most important single aspect of code organization.” The section on interfaces has about twenty rules. Four of the rules are related to contracts, which didn’t make it into the C++20 standard.

A few rules related to interfaces involve contracts, which may be part of C++23. A contract specifies preconditions, postconditions, and invariants for functions that can be checked at run time. Due to the uncertainty of the future, I ignore these rules. The appendix ...