[texhax] part and showkeys

[bnb at ams.org]

On Mon, 1 Jun 2015, Victor Ivrii wrote:

    If I enable showkeys and label part then an extra page is created after the
    title page of the part and on this page only label of part is displayed.
    Surely it is not a big deal as in the final production showkeys is not
    active but still it seems to be a bug. It happens with both book and memoir
    classes ; Checked with TL2014 and TL2015 (prerelease)

    \documentclass[12pt,oneside]{memoir}
    \usepackage[color]{showkeys}

    \usepackage{hyperref}
    \usepackage{blindtext}
    \begin{document}
    \part{Part One}
    \label{part-1}
    \chapter{Chapter One}
    \blindtext[3]
    \end{document}

the problem is that the definition of
\part itself contains the instruction
for a new page, which of course would
take effect before showkeys can operate
on the label.  in book.cls:

  \def\@endpart{\vfil\newpage
              \if at twoside
               \if at openright
                \null
                \thispagestyle{empty}%
                \newpage
               \fi
              \fi
              \if at tempswa
                \twocolumn
              \fi}

so it's not an implementation problem
on the part of showkeys, it's a design
problem.  not quite sure how to go
about getting around it.

actually, things are even worse with
both book and memoir: if twoside is
specified, page 2 is blank, the label
report is on page 3, page 4 is blank,
and chapter 1 doesn't start until
page 5.  a mess.  (amsbook has the
problem as reported when oneside is
specified, but with twoside, the
label report is on page 2, and the
chapter starts on page 3.  still a
mess with respect to showkeys.)
					-- bb