I use this alot but I have never been able to understand exactly what was going on it there

this is called cargo-cult programming. be very careful of this practice. as stated in that link,

One of our illustrious members once had the habit of crying "cargo cult!" whenever he saw someone cut and paste a code snippet into a program. In particular, he was decrying the habit of cutting and pasting bad code. But even cutting and pasting good code is not necessarily a good thing.

this code is bad for maintainence, because it's fragile. its not obvious at first glance that the quoted words are assigned to the lvalues, because they're mapped through an obfuscated route.

better alternatives include the translations provided by swiftone and Chmrr, especially Chmrr's. it's straight forward, direct, and its format allows easy modification.

although your code provides an interesting use of anonymous data structures and slices, i would never use it in production code.

~Particle ;Þ