Javascript

Functions

• Functions are tools that allow you to re-use code easily without needing to write it over and over.
• It keeps your code DRY (don't repeat yourself)
• They can save a lot of time if you need to do something repeatedly!
• Defining a function:

  function listSomethingFiveTimes(something) {
    for (var i = 0; i < 5; i++) {
      console.log(something);
    }
  }
  

• Returning a value from a function:

  function addOne(myNumber) {
    return myNumber + 1;
  }
  var x = addOne(4);
  // x will equal 4 + 1
  // x equals 5
  

• Scope inside of a function. The xbox variable is not accessible outside of that function because it is only inside of the scope of the function named double's scope.

  function double(num) {
  var xbox = "eh ok";
  // some other code here
  }