Parameters

Defining parameters

A parameter is a placeholder for a value which will be supplied later.

function addNumbers(x, y) {
  return x + y
}

Using parameters

When calling a function, we provide arguments for the parameters.

js

function addNumbers(x, y) {
  return x + y
}

console.log(addNumbers(2, 3))
console.log(addNumbers(14, -20))

// even like this
const a = 134
const b = 201
console.log(addNumbers(a, b))

output

5
-6
335

Early return

The return keyword can end a function early.

js

function logInUser() {
  // this will get printed
  console.log('User is logged in.')

  // the function stops here (early return)
  return true

  // this code will never run
  console.log('awww :(')
}

output

User is logged in.