Intro to ABC

So, the ABC format is a simple ASCII format designed primarily to make it easy to work with single line musical notation. It's great for, say, traditional dance tunes, like this tune from Northumberland.

X:64
T:Cuckold Come Out o' the Amrey
S:Northumbrian Minstrelsy
M:4/4
L:1/8
K:D
A/B/c/A/ +trill+c>d e>deg | GG +trill+B>c d/B/A/G/ B/c/d/B/ |
A/B/c/A/ c>d e>deg | dB/A/ gB +trill+A2 +trill+e2 ::
g>ecg ec e/f/g/e/ | d/c/B/A/ Gd BG B/c/d/B/ | 
g/f/e/d/ c/d/e/f/ gc e/f/g/e/ | dB/A/ gB +trill+A2 +trill+e2 :|

My favorite ABC program renders that like this (click on it for a high resolution version):


So, my goal here is to write a Perl 6 module that can read and understand this format, maybe do some light processing, and output it again. I'm hoping a grammar will make this pretty easy and straightforward, but I'm fairly ignorant of them so far. It will be an adventure!

I guess my first step is to set up a class to represent a tune, and then write some tests for it. Next time...