A synchronous embedding of Antescofo, a domain-specific language for interactive mixed music

Antescofo is recently developed software for musical score following and mixed music: it automatically, and in real-time, synchronizes electronic instruments with a musician playing on a classical instrument. Therefore, it faces some of the same major challenges as embedded systems. The system provides a programming language used by composers to specify musical pieces that mix interacting electronic and classical instruments. This language is de-veloped with and for musicians and it continues to evolve according to their needs. Yet its semantics has only recently been formally defined. This paper presents a synchronous semantics for the core language of Antescofo and an al-ternative implementation based on an embedding inside an existing synchronous language, namely ReactiveML. The semantics reduces to a few rules, is mathematically precise and leads to an interpretor of only a few hundred lines. The efficiency of this interpretor compares well with that of the actual implementation: on all musical pieces we have tested, response times have been less than the reaction time of the human ear. Moreover, this embedding permitted the pro-totyping of several new programming constructs, some of which are described in this paper