A publish/subscriber pattern (in short pub-sub) is sometimes also referred to as Event Aggregation. In this pattern, different components of the application communicate with a topic/event channel. When using this pattern, the components of the application are loosely coupled. Unlike observer pattern where all the observers depend on the notifications from a subject, in the
According to the GoF book, Design Patterns: Elements of Reusable Object-Oriented Software, the definition of Observer Pattern is: “One or more observers are interested in the state of a subject and register their interest with the subject by attaching themselves. When something changes in our subject that the observer may be interested in, a notify
At first, it would seem that the singleton pattern is similar to the module/revealing module pattern where we create only one instance of the object. However, the difference here is we can delay the instantiation of the object, i.e. based on the requirement. The singleton pattern restricts the instance of an object (class) to one.
In the constructor pattern, we create an object using constructor functions, but in the module pattern, we use the object literals. We already know the ways to create an object, if you’d like to read about it, click here. Creating an object using object literals is a simple task. We need to provide the key-value
The constructor pattern in JavaScript is the simplest one perhaps. All we need to do is to create a constructor function, add properties and methods to it. It’s ready to use. There are lots of blogs on the internet about what are design patterns, why should we use them, how they make developers lives simple,
