From 7b136e0a65814d8bfd93bedbef2096efb9af1213 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20Ke=C3=9Fler?= <git@maximilian-kessler.de>
Date: Tue, 18 Jan 2022 00:15:02 +0100
Subject: [PATCH] implement theorem group rules

---
 doc/environments/groupthm/groupthm.dtx | 65 ++++++++++++++++++++++++--
 doc/environments/groupthm/groupthm.sty |  2 +-
 2 files changed, 63 insertions(+), 4 deletions(-)

diff --git a/doc/environments/groupthm/groupthm.dtx b/doc/environments/groupthm/groupthm.dtx
index 9d0ecb6..e20cdf9 100644
--- a/doc/environments/groupthm/groupthm.dtx
+++ b/doc/environments/groupthm/groupthm.dtx
@@ -785,6 +785,15 @@
 %
 %
 %
+% \begin{function}{\groupthm_declare_theorem_group_rule:nnnn}
+%    \begin{syntax}
+%       \cs{groupthm_declare_theorem_group_rule:nnnn}\ma{keyname}\ma{theorem group 1}
+%       \ma{relation}\ma{theorem group 2}
+%    \end{syntax}
+%
+%  \LaTeX3 version of \cs{DeclareTheoremGroupRule}
+%
+% \end{function}
 %
 %
 %
@@ -1492,8 +1501,59 @@
 %    \end{macrocode}
 % \end{macro}
 %
-% 
-% 
+% We also provide the interface for declaring the precedence rules for theorem groups.
+%
+%
+% \begin{macro}{\groupthm_declare_theorem_group_rule:nnnn}
+%    \begin{syntax}
+%       \cs{groupthm_declare_theorem_group_rule:nnnn}\ma{keyname}\ma{theorem group 1}
+%       \ma{relation}\ma{theorem group 2}
+%    \end{syntax}
+%		 
+% We have to normalize the arguments a little bit, namely replacing \texttt{higher}
+% and \texttt{lower} with \texttt{before} \texttt{after} respectively,
+% and prefix the \meta{keyname} with \texttt{__groupthm}
+% in case it is not the general hook \enquote{\texttt{??}}.
+%
+%    \begin{macrocode}
+\cs_new:Npn \groupthm_declare_theorem_group_rule:nnnn #1 #2 #3 #4
+  {
+    \str_set:Nx \l_tmpa_str { \tl_trim_spaces:n { #3 } }
+
+    \str_if_eq:VnT \l_tmpa_str { higher }
+    {
+      \str_set:Nn \l_tmpa_tl { after }
+    }
+
+    \str_if_eq:VnT \l_tmpa_str { lower }
+    {
+      \str_set:Nn \l_tmpa_tl { before }
+    }
+
+    \str_if_eq:nnTF { #1 } { ?? }
+    {
+      \hook_gset_rule:nnVn {??} {#2} \l_tmpa_tl {#4}
+    }
+    {
+      \hook_gset_rule:nnVn { @@ / #1 } {#2} \l_tmpa_tl {#4}
+    }
+  }
+%    \end{macrocode}
+% \end{macro}
+
+% \begin{macro}{\DeclareTheoremGroupRule}
+%    \begin{syntax}
+%      \cs{DeclareTheoremGroupRule}[\meta{keyname}]%
+%      \{\meta{theorem group 1}\}\{\meta{relation}\}\{\meta{theorem group 2}\}
+%    \end{syntax}
+%
+%    \begin{macrocode}
+\NewDocumentCommand { \DeclareTheoremGroupRule } { O{??} m m m }
+  {
+    \groupthm_declare_theorem_group_rule:nnnn {#1} {#2} {#3} {#4}
+  }
+%    \end{macrocode}
+% \end{macro}
 % 
 % 
 % \subsection{Grouped Theorems} 
@@ -1509,4 +1569,3 @@
 %   \end{implementation}
 % \end{documentation}
 % \newpage
-% \PrintIndex
diff --git a/doc/environments/groupthm/groupthm.sty b/doc/environments/groupthm/groupthm.sty
index 6126871..6f6defb 100644
--- a/doc/environments/groupthm/groupthm.sty
+++ b/doc/environments/groupthm/groupthm.sty
@@ -20,7 +20,7 @@
 %% original source files, as listed above, are part of the
 %% same distribution. (The sources need not necessarily be
 %% in the same archive or directory.)
-%% File: l3prop.dtx
+%% File: groupthm.dtx
 \ProvidesExplPackage{groupthm}{2022/01/17}{0.0.1}{Grouped theorems.}
 \RequirePackage{amsthm}
 \RequirePackage{thmtools}