[SOLVED] Can't use patterns for Pfx arguments?

Questions
1

I’ve been trying to use patterns for Pfx arguments, but they are not working. Is that even possible?
Here’s (part of) the code:

(
Pdef(\a,
	Pfxb(
		Ppar([
			Pbind(\instrument, \white),
		]),
		\lpf,
		\freq, Pseq([400, 4400],inf),
	)
).play;
)
2

See PbindFx from miSCellaneous_lib

3

Grand! Thanks @dkmayer!