This demo introduces Tonart, a language and metalanguage for practical music composition. The object language of Tonart is abstract syntax modeling a traditional musical score. It is extensible- composers choose or invent syntaxes which will most effectively express the music they intend to write. Composition proceeds by embedding terms of the chosen syntaxes into a coordinate system that corresponds to the structure of a physical score. Tonart can easily be written by hand, as existing scores are a concrete syntax for Tonart. The metalanguage of Tonart provides a means of compiling Tonart scores via sequences of rewrites. Tonart’s rewrites leverage context-sensitivity and locality, modeling how notations interact on traditional scores. Using metaprogramming, a composer can compile a Tonart score with unfamiliar syntax into any number of performable scores.

In this demo, we will make a small composition using Tonart. We will construct this composition by manipulating notations representing abstract music objects. These will eventually be compiled into a digital score representation, as well as a computer performance. We will add in an especially abstract object at the end, and use our creativity to compile it into something performable.