Make \upbow an empty command + Segmentation fault

[Felix Janda]

Hi,

say I have a violin part with bowing instructions in a variable. Now I want
to use the same variable in the full orchestral score but the bowing marks
should be suppressed.

\upbow is treated by lilypond as an articulation, but the other
articulations should be unaffected by the suppressing of \upbow.

upbow={}

doesn't work because it breaks things like

a\upbow ~ a

Playing a bit with the definition of \upbow gave me a segfault.
Minimal example:


\version "2.18.0"

upbow = #(make-music 'ArticulationEvent
                     'articulation-type "upbow" 'types #f)
downbow = \upbow


Anyway, how do I make a command which has no effect at all?

Cheers,
Felix