variables

Hey Kirby!

Here's the short version:

var example;  <- example = undefined

var example = "";

When you instantiate the variable without assigning a value, the value of that variable is undefined. When you set the variable to an empty string (""), this is actually defining a value for the variable which is just the empty string.

If you open the console in your browser (for me in Chrome, right-click, Inspect Element, go to Console tab), you can type JavaScript there and see immediate feedback. If you type var example;, you'll see what I'm talking about where it returns undefined.

Hope that helps!

Parker

Both are valid, the top will simply have a value of 'undefined', and the bottom will be an empty string. If you aren't going to be using the initial value, and you aren't going to be testing the type the variable with the 'typeof' operator or something, then declaring it without a value is fine.

Leaving a variable undeclared is okay in javascript since we don't have to cast a variable as a type. Usually when you see it, it just means the coder plans to use it later without littering the script with 'var'.

For example:

var a, b, c;
//instead of:
var a;
var b;
var c;
//or
var a = 0;
var b = "";
var c = [];

Thanks guys! Its clear now.

Thumbs up to you both.