Re: Bar lines

[David Kastrup]

Marc Hohl <address@hidden> writes:

> Am 06.03.2013 09:38, schrieb David Kastrup:
>> Marc Hohl <address@hidden> writes:
>>
>>> kudos for this detailed explanation! I wonder if the documentation about
>>> bar lines should be enhanced in this way, or is there a place where this
>>> information can be stored and made available for all users?
>>
>> It is orthogonal to us making \bar "|:" and \bar ":|" well-defined by
>> letting : automatically imply a thick bar since nothing else makes
>> sense.
>
> I don't think that this is the problem Joram struggled with.

To quote:

    \defineBarLine "|:" #'(":||" "" "|:")   % a)
    \defineBarLine ":||" #'(":.." "" " ||") % b)

    \new StaffGroup <<
      \new Staff { a1 \bar "|:" a \bar "|:" }
      \new Staff { f'1 f' }
    >>

So he is defining a bar type "|:" himself.  To further quote:

    4) Would it make sens to have a fourth bar line situation (besides
    in a line, end of line, start of line): The final bar line at the
    very end of a staff?

With the "pure" approach of the barline interface this question should
not even be possible since _iff_ end of staff is to be treated
differently, the user is expected to pick a different bar type himself.

> If the majority of users and developers think that explicitly using
> the dot "." for a thick bar line is suboptimal, then
>
> cced43289cf170305e6e6517180659a1c4fa91db
>
> should never have happened. Feel free to revert it.

That commit is

commit cced43289cf170305e6e6517180659a1c4fa91db
Author: Marc Hohl <address@hidden>
Date:   Wed Aug 1 21:15:46 2012 +0200

    New bar line interface
    
    * the input string of a bar line called by \bar "<bar string>" resembles the
    
    * (define-bar-line ...) or \defineBarLine allows for new definitions. These 
      the bar line itself, the bar line used at the end of line, the bar line us
    
    * Annotations for barlines can be added to distinguish between two identical
      apperance or span bar lines.
    
    * To align span bars properly, the space character " " has a
      special meaning. When it occurs, the width of the resembling glyph in the 
    
    * New glyphs can be added easily.
    
    * Volta brackets take the bar line dimensions into account.


and is not at all constrained to changing \bar "|:" to \bar ".|:".  I
don't think we have a policy that features may only be removed
completely rather than fixed.

> I for myself use \repeat volta ... without having to cater for
> manual repeat bar lines at all ;-)

Not exactly an endorsement.

-- 
David Kastrup