Re: Double thin bar lines and repeats?

[Thomas Morley]

2015-01-20 0:43 GMT+01:00 Lars-Johan Liman <address@hidden>:
> address@hidden:
>> Try:
>> \bar ".|:-||"
>
> Thanks a bunch! That does indeed work. If you ever need a trick or two
> from the advanced DNS trick book, I'll be happy to repay you ... :-)
>
>> It's in the NR ;)
>
> I did find that part, but that is, however, not how I understood it. :-P
>
> Can you also explain why it's needed? Why doesn't the
>
> \bar "||" \break
> \repeat 2 { ... }
>
> work? I _do_ realise that repeat marks at the beginning of the entire
> piece aren't supposed to be printed, but this is not the case.
>
> Does the \bar "||" (or \break?) signal something to LilyPond (which \bar
> "|" doesn't) like "end-of-phrase", that makes it treat the next line as
> the beginning of a (sub?-)piece?  But that doesn't make sense either,
> because another hint in the NR describes how to actually put repeat
> marks at the very beginning, and that only works at the VERY beginning,
> _not_ after the "||".
>
> Happier, but still confused, and only at a slightly higher level ... :-)
>
> But I need sleep. Badly ... :-)
>
>                                 Cheers,
>                                   /Liman

Well, _every_ BarLine has some settings in the definition how to
behave mid-line, line-begin, line-end and for the span-bar-type.

\bar "||" doesn't print a bar-line at line-begin (see bar-line.scm)

The \repeat construct uses the value from 'startRepeatType' (see
engraver-init.ly) as starting repeat-sign, default and fall-back is
".|:" (see repeat-acknowledge-engraver.cc and look up how ".|:" is
defined in bar-line.scm)

While inputting
\bar "||" \break \repeat volta ...
you have two _conflicting_ settings at the _same_ musical moment.
One will override the other.
Clean sollution is to define a BarLine which has the settings you
prefer. This is done already with the predefined ".|:-||" (again, see
bar-line-scm).

Only thing I don't fully understand, why does "||" wins?
I'd expect the ".|:" to be printed.

Maybe of the internal representation of the music?

look at the terminal-output of:

\displayMusic
{
 R1
 \bar "||"
 \break
 \bar ".|:"
 R1
}

\displayMusic
{
 R1
 \bar "||"
 \break
 \repeat volta 2 { R1 }
}

Not enough knowledge, though.

Cheers,
  Harm