Looping Programs?

So I've recently written a simple program for a felling turtle to,well, cut down a Spruce Tree, I have gotten everything working up to this point. i need the turtle to forever (until terminated) repeat this program that I've simply named "spruce". I'm tried "while true do spruce end" (without quotations and in lua,of course) but it just hasn't worked. Craft OS 1.5 help only please.

Instead of the word "spruce", try sticking the rest of your script into that "while" loop.