Question

Short questioion, I’m trying to understand this tutorial:
http://superdit.com/2011/02/09/jquery-memory-game/

Being new to Javascript I can’t seem to find what the statement ‘== “”‘ means… I understand “==”, but not the empty double quotes.

Answer 1

val == "" is a non-strict comparison to emtpy string. It will evaluate to true if val is empty, 0, false or [] (empty array):

var val = "";
console.log( val == "" ); // true

val = 0;
console.log( val == "" ); // true

val = false;
console.log( val == "" ); // true

val = [];
console.log( val == "" ); // true

You can use === to use strict comparison, fex:

val = 0;
console.log( val === "" ); // false