Bind and call

bind.js

let person1 = {
  name: 'Ben'
}

let person2 = {
  name: 'Christina'
}

function logName() {
  return this.name;
}

console.log(logName());
// returns an undefined
console.log( logName.bind(person1)() );
// call function bind object and call function
console.log( logName.bind(person2)() );

let number = {
  x: 24,
  y: 22
}

let count = function() {
  console.log(this.x + this.y); //no this context here
}

count();

let boundCount = count.bind(number);

boundCount();

call.js

let obj = {
  num: 2
}

let addToThis = function(a, b, c) {
  return this.num + a + b + c;
}

// call binds the function to the first object passed in
// parameter are passed in subsequent values

console.log(addToThis.call(obj, 1, 2, 3));

let person1 = {
  firstName : 'Jack',
  lastName: 'Davis'
}

let person2 = {
  firstName : 'Mark',
  lastName: 'Price'
}

function hello(greeting) {
  console.log(`${greeting} ${this.firstName} ${this.lastName}`);
}

hello.call(person1, 'Hello');
hello.call(person2, 'Fuck off!');