Yes, of course, but the typesetting language _itself_ doesn't have this,
right? I can also do:
\begin{verbatim}
for (i = 0; i < 10; i++)
{
foo ();
}
\end{verbatim}
in TeX, but that doesn't make it _programming_. If TeX or the music
typesetting stuff _does_ have this capacity, that would be interesting.
In fact, I think functional / procedural sequencing is pretty neat in
itself, although I don't know much about it at all, if it leads to
anything musical, if it's a well-known technique, etc. etc.