Adding a lyrics extender line to an alternate ending

[Risto Vääräniemi]

Hi,

Can anyone tell me if there's a way to print a lyrics extender line in
the beginning of the alternate ending? Please, have a look at the
image and the example to get a better view what I mean.

I tried to use underscores but they were not vertically aligned with
the extender line. It also seems that there are small gaps between
them. I've tried some other tricks, too, but they didn't work.

-Risto

%%%% Start %%%%
\version "2.11.37"

\paper { ragged-right = ##t }

{
    \repeat volta 2 {
    c'2 c'2 ~ } \alternative {{
    c'1}{
    c'2\repeatTie c''2 }}
    \bar "|."
}
\addlyrics { Tra la __ "___" lah. } % not quite
%\addlyrics { Tra la __ "" __ lah. } % does't work
%\addlyrics { Tra la __ " " __ lah. } % does't work
%%%% END %%%%

extender_line_for_2nd_ending.png
Description: PNG image