Re: NR 3.2.3 Reference to page numbers - buggy? (issue 884)

[Colin Campbell]

On Wed, 2010-12-29 at 00:49 +0000, Neil Puttock wrote:
> On 27 December 2010 17:58, Jean-Charles Malahieude <address@hidden> wrote:
> 
> > May I guess that it is due to \mark falling before the first note event
> > is generated?
> 
> No.  It's a consequence of the way label-page-table is generated;
> since 2.13.5 the order is consistently reversed, leading to \page-ref
> accessing the first entry for markA.  Here's the output for
> label-page-table in 2.12 and 2.13:
> 
> (2.12.3)
> ((markA . 2) (markTheEnd . 2) (firstScore . 1) (markA . 1))
> 
> (2.13.45)
> ((firstScore . 1) (markA . 1) (markA . 2) (markTheEnd . 2))
> 
> Of course, this means that in 2.12 the following snippet is also
> wrong, so it would be incorrect to assume this bug is a regression:
> 
> \book {
>   \label #'firstScore         %% page 1
>   \score {
>     {
>       c'1
>       \label #'markA % still page 2, due to alist order in label-page-table
>       \pageBreak
>       \mark A   %% page 2
>       c'1 \label #'markTheEnd %% page 2
> 
>     }
>   }
> 
>   \markup { The first score begins on page \page-ref #'firstScore "0" "?" }
>   %% prints page 1
> 
>   \markup { Mark A is on page \page-ref #'markA "0" "?" }
>   %% prints page 2
>   \markup { Finish line on page \page-ref #'markTheEnd "0" "?" }
>   %% prints page 2
> }
> 
> Due to the way labels are generated inside a score (using paper
> columns), the concept of a label at a page break is dubious: the same
> NonMusicalPaperColumn is on two pages (at the end of the last system
> before the break, and the start of the next system after the break),
> hence the duplicated page marker you see in the output for
> label-page-table above.
> 
> Cheers,
> Neil

I've just copied your snippet into Frescobaldi, and added a couple of
\version statements so I can change versions with a comment. Using
2.12.3 the snippet reports page 2 for markA and under 2.13.44 it is on
page 1. Also, the \book block is not part of the problem.

It may be that this is a Doc fix, explaining the use of labels at page
breaks, but since the behaviour has clearly regressed, I'll raise a new
issue.

Colin
-- 
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