Call rules within a rule?

Is there a way to call a specific technique or rule within the rules file? For example, several GPO keyswitches allow for playable trills or tremolos. I was thinking of writing a rule for these instruments that calls for a sixteenth note tremolo while shortening the individual sixteenth notes in half to allow for the playable trill to sound. Shortening the note is a fairly simple process, but I'm not sure how to call a tremolo effect from within the rules file; is this possible?
Please let me know if you need more details or a better explanation.
Please let me know if you need more details or a better explanation.