[latex3-commits] [git/LaTeX3-latex3-latex2e] metadata: add Ulrike's updates (5865f50d)

[Frank Mittelbach]

Repository : https://github.com/latex3/latex2e
On branch  : metadata
Link       : https://github.com/latex3/latex2e/commit/5865f50d8d43e9d85a4a31029fb76ff4e9a69407

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

commit 5865f50d8d43e9d85a4a31029fb76ff4e9a69407
Author: Frank Mittelbach <frank.mittelbach at latex-project.org>
Date:   Sat Dec 18 00:20:20 2021 +0100

    add Ulrike's updates


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

5865f50d8d43e9d85a4a31029fb76ff4e9a69407
 required/latex-lab/documentmetadata-support.dtx | 26 ++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/required/latex-lab/documentmetadata-support.dtx b/required/latex-lab/documentmetadata-support.dtx
index e62d3deb..1fffb76d 100644
--- a/required/latex-lab/documentmetadata-support.dtx
+++ b/required/latex-lab/documentmetadata-support.dtx
@@ -128,17 +128,17 @@
 %    \end{macrocode}
 %
 %    The wanted backend must be detected first, we read the init
-%    key and then force the loading by either loading l3pdf (+ expl3)
-%    or only expl3.  The backend contains now management command, so
-%    the boolean should true first.
+%    key and then force the loading of the backend.
+%    The backend can contain management commands, so the boolean should
+%    be set to true first.
 %    \begin{macrocode}
-        \keys_set_groups:nnn { document / metadata} {init}{ #1 }
-        %should be loaded after the backend is set, and only if not in the kernel
         \bool_gset_true:N \g__pdfmanagement_active_bool
-        \cs_if_free:NTF \pdf_uncompress:
-           {\RequirePackage{l3pdf}}
-%FMi why load expl3? is there a better way to force the backend loading?          
-           {\RequirePackage{expl3}}
+        \keys_set_groups:nnn { document / metadata} {init}{ #1 }
+        %if no backend has been loaded force it now:
+        \str_if_exist:NF \c_sys_backend_str
+          {
+            \sys_load_backend:n {}
+          }
 %    \end{macrocode}
 %    Now we load the extra backend code:
 %    \begin{macrocode}
@@ -205,11 +205,11 @@
 
 \keys_define:nn { document / metadata }
   {
-     backend .code:n =
+     backend .choices:nn =
+       { dvipdfmx , dvips , dvisvgm , luatex , pdftex , pdfmode , xdvipdfmx , xetex }
        {
-         \PassOptionsToPackage { driver=#1 } {expl3}
-         \AddToDocumentProperties[document]{backend}{#1}
-       }
+        \sys_load_backend:n {#1}
+      },
     ,backend .groups:n = { init }
     ,pdfversion .code:n =
       {