Objects

Dicts are objects, access members with ['name'] or .name

var person = {}; //{} 
var person1 = new Object();

Iterate Over

Object.keys(p).map(k => )
Object.entries(p).map(([k, v]) => )
Object.values(p).map(v => )

for (let key of Object.keys(players)) {
    //.......
}

General

Check in

'x' in {'x': 1} //true

Combine Objects

Objects/keys on the right override those to the left

{...x, ...y, ...z, a: 1}
Object.assign(x, y, z) //

Copy

{...x}
Object.assign({}, x)

Delete

delete myObject.prop;

Equality

=== will do ptr equality

Use lodash .isEqual for deep equality

Old Classes

function Person(name) {
  this.name = name;
  this.greeting = function() {
    alert('Hi! I\'m ' + this.name + '.');
  };
}

var person1 = new Person('Bob'); //new returns obj
var person2 = new Person('John'); //contains a new definition of gretting

To define functions out of scope,

function Test(a, b, c, d) {
  // property definitions
}

// First method definition
Test.prototype.x = function() { ... };

// Second method definition
Test.prototype.y = function() { ... };

Can always add new values

person1.newv = "secretsss";

Prototypes?

objects can have a prototype object that all instances inherit from, everyone inherits from object prototype

Person.prototype
Object.prototype

Changes to prototype affect all people

Person.prototype.farewell = function() {
  alert(this.name.first + ' has left. Bye for now!');
};
person1.farewell();

Create

Object.create makes a new object with the object given as its prototype, basically defining a subclass

var person3 = Object.create(person1);//copy constructor, (inherit from person1)

Inheritance

Its a mess, stupid javascript didn't want to do this

function Teacher(first, last, age, gender, interests, subject) {
    Teacher.prototype = Object.create(Person.prototype); //inherit from Person.prototype
    Teacher.prototype.constructor = Teacher; //you just replaced the constructor, add it back
    Person.call(this, first, last, age, gender, interests); //.call allows you to pass this setting it

  this.subject = subject;
}