TabNoteHeads in tie/slur or tie/glissando combinations

[Marc Hohl]

Hello all,

lilypond handles tied notes within a TabStaff (almost) correctly, but I 
ran into problems
with combinations of tie/slur or tie/glissando combinations.

Consider this example:

\version "2.13.33"

test = {  d4 ~ d (  e2 ) | d4 ~ d \glissando e2 | }

\score {
 <<
 \new Staff { \clef "G_8" \test }
 \new TabStaff { \test }
 >>
}

The second note in each measure should not disappear in such cases, but 
rather
be displayed in parentheses, in the second measure for example like 
this: 0 (0) / 2

Is there a possibility to check whether a note head is the right bound 
of a tie
AND the left bound of a slur or a glissando?
I thought about checking for the TabNoteHead #'transparent value for the 
left bound,
but this would not work in cases where the user wanted to make the note 
heads
explicitly invisible (i.e. for the simulation of chord glissandos via 
additional helper
voices with invisible note heads), so I assume it is not that simple. 
Any ideas?

Thanks in advance

Marc