[latex3-commits] [git/LaTeX3-latex3-latex3] master: Add \hbox_overlap_center:n (a23a90dae)

[Joseph Wright]

Repository : https://github.com/latex3/latex3
On branch  : master
Link       : https://github.com/latex3/latex3/commit/a23a90dae20022327c7773aba03026699f9fb1e0

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

commit a23a90dae20022327c7773aba03026699f9fb1e0
Author: Joseph Wright <joseph.wright at morningstar2.co.uk>
Date:   Tue Aug 25 15:53:29 2020 +0100

    Add \hbox_overlap_center:n


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

a23a90dae20022327c7773aba03026699f9fb1e0
 l3kernel/CHANGELOG.md |  3 +++
 l3kernel/l3box.dtx    | 12 +++++++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/l3kernel/CHANGELOG.md b/l3kernel/CHANGELOG.md
index 304b59381..709635486 100644
--- a/l3kernel/CHANGELOG.md
+++ b/l3kernel/CHANGELOG.md
@@ -7,6 +7,9 @@ this project uses date-based 'snapshot' version identifiers.
 
 ## [Unreleased]
 
+### Added
+- `\hbox_overlap_center:n`
+
 ### Fixed
 - `\file_compare_timestamp:nNn(TF)` in LuaTeX (issue #792)
 
diff --git a/l3kernel/l3box.dtx b/l3kernel/l3box.dtx
index 8adeb3fb6..fd33cd58c 100644
--- a/l3kernel/l3box.dtx
+++ b/l3kernel/l3box.dtx
@@ -370,6 +370,14 @@
 %   and then stores the result inside the \meta{box}.
 % \end{function}
 %
+% \begin{function}[added = 2020-08-2505]{\hbox_overlap_center:n}
+%   \begin{syntax}
+%     \cs{hbox_overlap_center:n} \Arg{contents}
+%   \end{syntax}
+%   Typesets the \meta{contents} into a horizontal box of zero width
+%   such that material protrudes equally to both sides of the insertion point.
+% \end{function}
+%
 % \begin{function}[updated = 2017-04-05]{\hbox_overlap_right:n}
 %   \begin{syntax}
 %     \cs{hbox_overlap_right:n} \Arg{contents}
@@ -1381,10 +1389,12 @@
 %  \end{macro}
 %  \end{macro}
 %
-% \begin{macro}{\hbox_overlap_left:n, \hbox_overlap_right:n}
+% \begin{macro}{\hbox_overlap_center:n, \hbox_overlap_left:n, \hbox_overlap_right:n}
 %   Put a zero-sized box with the contents pushed against one side (which
 %   makes it stick out on the other) directly into the input stream.
 %    \begin{macrocode}
+\cs_new_protected:Npn \hbox_overlap_center:n  #1
+  { \hbox_to_zero:n { \tex_hss:D #1 \tex_hss:D } }
 \cs_new_protected:Npn \hbox_overlap_left:n  #1
   { \hbox_to_zero:n { \tex_hss:D #1 } }
 \cs_new_protected:Npn \hbox_overlap_right:n #1