Hierachical Finite State Machines
In this post I talk about hierarchical state machines and present a simple implementation, based on the state pattern. It is by no means a comprehensive explanation, and I skim...
Category: Design Patterns
C++ delegates
In a previous article I wrote about the ubiquitous observer pattern, which is all about objects (called observers or listeners) that need to be notified when other objects in the...
Strategy Desing Pattern and variadic class templates
The Strategy design pattern is a perfect example of the OOP tenet that says: “favor composition over inheritance”. Inheritance is indeed powerful when it comes to code reuse, or when...
State Design Pattern
Many systems wait continuously for the occurrence of some event, and they react to the event by performing computations or changing their state. Once the event is handled, they go...
Composite Design Pattern
According to the GoF book, the intent of the Composite pattern is to “compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions...
Observer Design Pattern
The Observer Pattern According to the GoF book the Observer pattern “defines a one to many dependency between objects so that when one object changes state, all its dependents are...
Command Design Pattern
The Command Pattern The Gang of Four’s book gives the following definition of the command pattern: “The Command pattern encapsulates a request as an object, letting you parameterize clients with...