How Does the `new` Keyword Work in JavaScript?

Understanding the 'new' Keyword in JavaScript

The concept of using 'new' in JavaScript can be perplexing, especially when considering JavaScript's non-object-oriented nature. To clarify, 'new' operates in the following ways:

1. Creating a New Object:

• It establishes a new object, which is fundamentally an object of the type "object."

2. Setting the Prototype:

• It associates the newly created object's inaccessible [[prototype]] property with the external prototype property of the constructor function. This inheritance relationship enables access to properties defined in the constructor's prototype.

3. Binding the 'this' Variable:

• It designates the 'this' variable to point to the newly created object, allowing for explicit access to its properties and methods within the constructor function.

4. Executing the Constructor:

• It runs the constructor function, using the newly created object as the context for 'this.'

5. Returning the Object:

• After execution, it returns the newly created object unless the constructor explicitly returns a different object.

Utilizing the 'new' Keyword:

• The appropriate scenario for using 'new' is when instantiating objects, usually when creating classes or simulating object-oriented behavior.
• It's not applicable when manually creating objects using object literals or hypothetical constructs.

Example:

function Constructor() {
  this.property = "value";
}

const object = new Constructor();

console.log(object.property); // "value"

Prototype Chain:

• Objects created with 'new' have a prototype chain.
• The [[prototype]] property of the sub-object's prototype points to the prototype property of the base constructor function.
• This chain allows for accessing inherited properties defined in the base constructor's prototype.

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