Ah finally solved. This was so much drama for a small thing to do. Problem: I have a string; SINCGKXXXYY . [Say these are 2 airport destinations + some junk text and i want to separate the airports out of the string in the easiest possible way!] Use the following extension:
var myCrappyJunkText:String = "SINCGKXXXYY"
var firstCode = myCrappyJunkText[0...2] //Should hold SIN
var 2ndCode = myCrappyJunkText[3...5] //Should hold CGK