A value object is a small object whose equality is based on state, but not identity. Typical value objects are money, numbers, or strings.

The concept of a regular type goes back to the creator of the Standard Template Library (STL) Alexander Stepanov. A regular type is a user-defined type and behaves like a built-in type.

The rule of zero, or six, is one of the advanced rules in modern C++. I wrote in my current book "C++ Core Guidelines Explained: Best Practices for Modern C++" about them. Today, I want to quote the relevant parts of my book in this post.

Argument-Dependent Lookup (ADL), also known as Koenig Lookup, is a set of "magical" rules for the lookup of unqualified functions based on their function arguments.

Partial Function Application is a technique in which a function binds a few of its arguments and returns a function taking fewer arguments. This technique is related to a technique used in functional languages called currying.

An idiom is an architectural or design pattern implementation in a concrete programming language. Applying them is idiomatic for a programming language. Today. I write about the Copy-and-Swap Idiom in C++. This idiom gives you the strong exception safety guarantee.

The Strategy Pattern is a behavioral design pattern from the book Design Patterns: Elements of Reusable Object-Oriented Software". It defines a family of algorithms and encapsulates them in objects.

The Template Method is a behavioral design pattern. It defines a skeleton for an algorithm and is probably one of the most often used design patterns from the book "Design Patterns: Elements of Reusable Object-Oriented Software".

The Visitor Pattern encapsulates an operation executed on an object hierarchy as an object and enables it to define new operations without changing the object hierarchy.

The Observer Pattern is a behavioral pattern from the book   "Design Patterns: Elements of Reusable Object-Oriented Software". It defines 1-to-n dependencies between objects so that changes to one object cause all dependent objects to be notified.