Is there a possibility to define a piece of music before score an call it by its name in score? Seems not. E.g. soprano = {e e e g2 f4 f f d2 }
and then \new Voice { \soprano}
see https://de.wikipedia.org/wiki/Benutzer:Roomsixhu/Tanzlied
first score form lilypond Handbook
That gives errormessages with wrong = and unknown string.
Cheers