Ties between Fingerings

[Noeck]

Hi,

can Lilypond draw ties between fingerings?
I can fake it by using a slur and putting it above the fingering:

\version "2.20.0"
{
  % fake what I want
  \override Fingering.avoid-slur = #'inside
  cis''-4( c''-4) r
  % ties possible on one note
  c''^\markup \finger \overtie "43"
}

Is that the way to go or is there a semantically correct way of
specifying ties between fingerings instead of notes?

Cheers,
Joram