Using Variables in a Tell Statement

I’m in the middle of writing an AppleScript Studio program that controls iTunes over the network. So far it plays, pauses, skips forward and back, shuffles, changes volume, mutes, switches playlists and shows the artist-title of songs in the current playlist in addition to the current song info, all of this is done perfectly as long as the machine address is hard coded:

tell application "iTunes" of machine "eppc://them.local"

But where is the fun in that? It makes it very difficult to release. However when I try making the machine address a variable:

property machineURL: "eppc://them.local"

tell application "iTunes" of machine machineURL

xCode, well osacompile, balks on compiling the source:

The interesting thing is that this type of code will work from within Script Editor.

Any ideas?

Figured it out. using terms from is your friend.