RemoveEmpty``Tab``StaffContext and 'internal properties'

[Vincenzo Colonnella]

Hi everybody!

I'm new to this list.
First of all, I want show all my gratefulness for the existence of such a 
beautiful program like Lilypond. I'm becoming an enthusiastic user of it... 
also if my usage isn't so extended. I'm studying it from some weeks and 
trying to know better how it works.
I'm using lilypond version 2.6.3.1 for Linux.

Unfortunately I don't have any experience in Scheme (studied only a bit of 
LISP some years ago).
Perhaps that would be useful to solve a problem which i'm fallen into. I know 
other people were, from the list archive. But I never found an answer to 
this, working for my case.
Problem concerns applying known command "\RemoveEmptyStaffContext" also to 
TabStaves.
The quoted command acts only on normal Staff objects, and not on TabStaff 
objects (someone suggested also DrumStaff, I don't know).
Others suggested a solution like this (I tried to adapt to my current version, 
any mistake??):

\context {
        \TabStaff
        \remove "Axis_group_engraver"
        \consists "Hara_kiri_engraver"
        \override Beam #'auto-knee-gap = #'()
        \override RemoveEmptyVerticalGroup #'remove-first = ##t
}

[   with version 2.6, I had to correct:
- usage of "consistsend": doesn't work, I used "consists";
- not usable in "paper" section: I used in "layout" section;   ]

That doesn't work for my sheet cause it remove all TabStaff lines!
At most, I can show only the first (empty) without "remove-first".

Wandering around Lilypond documentation, I figured out that a good solution 
would be about hacking a bit something in order to correctly set an "internal 
property".
'Hara_kiri_engraver' create a layout object called 'RemoveEmptyVerticalGroup', 
that supports the interface 'hara-kiri-group-interface', that contains the 
internal property 'items-worth-living'.
I think that the list defined in that property doesn't contain 
"TabNoteHeads", while perhaps it should.

Finally, my question: there's a way to manipulate also "internal properties" 
from a .ly source?
Or, at least, there's another working method to reach what I aim?


Thanx for patience!!
Greetings! And good work!! Go on so great!!

Vincenzo