When in doubt read the core, it's surprisingly well documented. :>
Code:
--[[ Runebar:
Author: Zariel
Usage: expects self.runes to be a frame, setup and positiononed by the layout itself, it also requires self.runes[1] through 6 to be a statusbar again setup by the user.
Options: (All optional)
.spacing: (float) Spacing between each bar
.anchor: (string) Initial anchor to the parent rune frame
.growth: (string) LEFT or RIGHT
.height: (int) Height of the bar
.width: (int) Width of each frame
]]