How to return an array of objects from a method in the same class javascript

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I am new to javascript. I want a class method to return an array of objects instantiated by the same class. How to do that?

Currently,Basically the following is the general structure my code in question.

class myClass{
   constructor(name,password,emailid,id) {
    this.name = name;
    this.password = password;
    this.emailid = emailid;
    this.id = id;
  }

  asyncMethod = async()=> {
     //method returns array of objects of same class
  }
}
object class javascript
1 Answers

On Class instantiation (constructor init), push the current instance to a class's static Array.
Retrieve all your instances by either using userInstance.getInstances() (← this is bad practice! Read further) or User.instances

class User {

  static instances = [];

  constructor(name, password, emailid, id) {
    this.name = name;
    this.password = password;
    this.emailid = emailid;
    this.id = id;
    User.instances.push(this); // Push instance into static Class's property
  }

  getInstances() {
    return User.instances; // Return array of instances of same Class
  }
}

const A = new User("Cada", "123", "c@c.c", 1);
const B = new User("Roko", "234", "r@r.r", 2);
const C = new User("John", "345", "j@j.j", 3);

console.log(A.name, B.name, C.name); // "Cada", "Roko", "John"
console.log(A.getInstances());  // [User, User, User]
console.log(myClass.instances); // [User, User, User]

Closely related answer: https://stackoverflow.com/a/61014433/383904

And I could not explain the static keyword better than MDN:

Neither static methods nor static properties can be called on instances of the class. Instead, they're called on the class itself. (*ac: myClass.instances in the above demo)
Static methods are often utility functions, such as functions to create or clone objects, whereas static properties are useful for caches, fixed-configuration, or any other data you don't need to be replicated across instances.

It's usually a bad practice to expose internals of a Class to an Instance.
For Example, a User instance should not be able to inherit from its Class constructor the entire list of Users.
Here's a slight variant that uses Static Private # and Class Getters get:

class User {

  static #_instances = []; // Static and private

  constructor(userData) {
    Object.assign(this, userData);
    User.#_instances.push(this);
  }

  static get instances() { // Static to Class
    return [...User.#_instances]; // exposes private (as immutable)
  }
}

const A = new User({name:"Cada", password:"123", emailid:"c@c.c", id:1});
const B = new User({name:"Roko", password:"234", emailid:"r@r.r", id:2});

console.log(A.name, B.name); // "Cada", "Roko",

console.log(A.instances);            // undefined 
console.log(User.instances);         // [User, User] 

User.instances.push({name:"EVIL!"}); //   
console.log(User.instances);         // [User, User]

user_3839040
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