[latex3-commits] [git/LaTeX3-latex3-latex2e] develop: Document that \ShipoutBox (255) is a local box - and always was, so should see no \global\setbox assignments (9fe7bf57)

[Frank Mittelbach]

Repository : https://github.com/latex3/latex2e
On branch  : develop
Link       : https://github.com/latex3/latex2e/commit/9fe7bf573180a88e673f9bbf6e400d2af4a3bf49

>---------------------------------------------------------------

commit 9fe7bf573180a88e673f9bbf6e400d2af4a3bf49
Author: Frank Mittelbach <frank.mittelbach at latex-project.org>
Date:   Wed Mar 17 16:19:59 2021 +0100

    Document that \ShipoutBox (255) is a local box - and always was, so should see no \global\setbox assignments


>---------------------------------------------------------------

9fe7bf573180a88e673f9bbf6e400d2af4a3bf49
 base/ltshipout.dtx | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/base/ltshipout.dtx b/base/ltshipout.dtx
index 565f35f5..f773cd23 100644
--- a/base/ltshipout.dtx
+++ b/base/ltshipout.dtx
@@ -33,7 +33,7 @@
 %
 %    \begin{macrocode}
 \providecommand\ltshipoutversion{v1.0i}
-\providecommand\ltshipoutdate{2021/01/25}
+\providecommand\ltshipoutdate{2021/03/17}
 %    \end{macrocode}
 %
 %<*driver>
@@ -144,6 +144,12 @@
 %    This box register is called \cs{ShipoutBox} (alternatively
 %    available via the L3 name \cs{l_shipout_box}).
 %
+%    This box is a ``local'' box and assignments to it should be done
+%    only locally. Global assignments (as done by some packages with
+%    older code where this is box is known as 255) may work but they are
+%    conceptually wrong and may result in errors under certain
+%    circumstances.
+%
 %    During the execution of \hook{shipout/before} this box contains
 %    the accumulated material for the page, but not yet any material
 %    added by other shipout hooks.