A documentation suggestion for glissandoMap

[Peter Toye]

I've found by experiment that there's something missing from NR 1.3.3 Glissando 
in the paragraph about glissandoMap.  This seems to imply that you need an 
entry for each note in a chord. But it's possible to leave out a gliss line 
entirely simply by omitting the relevant entry which is useful if two notes are 
the same.
 
I suggest appending to the paragraph: 'Each glissando line is represented by an 
entry in the glissandoMap; unwanted lines are omitted.'
 
And appending to the music example: 
 
    \set glissandoMap = #'((1 . 2) (2 . 1))
    <c f a>1\glissando |
    <c e c'>
 
Regards,

Petermailto:lilypond@ptoye.com
www.ptoye.com