implement option interface for groupthm.

src/environments/groupthm/groupthm.dtx

@@ -836,6 +836,7 @@
 %    \begin{macrocode}
 \RequirePackage{amsthm}
 \RequirePackage{thmtools}
+\RequirePackage{l3keys2e}
 %    \end{macrocode}
 %
 % \begin{macro}{\@@_thmtools_declare_theorem:nn, \@@_thmtools_declare_theorem:Vn}
@@ -965,6 +966,9 @@
 \hook_new:n { @@/thmtools  }
 %    \end{macrocode}
 %    \begin{macrocode}
+\hook_new:n { @@/definelazy }
+%    \end{macrocode}
+%    \begin{macrocode}
 \hook_new:n { @@/groupsort }
 %    \end{macrocode}
 %
@@ -1047,6 +1051,10 @@
 \bool_new:N  \l_@@_in_family_options_environment_bool
 %    \end{macrocode}
 % \end{variable}
+% 
+% 
+% 
+% 
 % \begin{variable}{\g_@@_append_groups_int}
 %		 
 %    This counts the number of times we appended to a group. 
@@ -1057,6 +1065,33 @@
 % \end{variable}
 %
 % 
+% 
+%
+% \begin{variable}{\g_@@_cache_bool}
+%		 
+%     This stores whether we cache definitions in the aux file.
+%
+%    \begin{macrocode}
+\bool_new:N \g_@@_cache_bool
+%    \end{macrocode}
+% \end{variable}
+% 
+% 
+%
+% \begin{variable}{\g_@@_cache_version_aux_int, \g_@@_cache_version_document_int}
+%		 
+%    The version of the cached theorems in the aux file
+%    and the version the package has been loaded with.
+%
+%    \begin{macrocode}
+\int_new:N \g_@@_cache_version_aux_int
+\int_new:N \g_@@_cache_version_document_int
+\int_set:Nn \g_@@_cache_version_aux_int { -1 }
+%    \end{macrocode}
+% \end{variable}
+% 
+% 
+%
 % \subsection{Key interface}
 % As mentioned, all keys will set their corresponding local variables
 % (containing \enquote{\texttt{_key_}} in their name) and store the
@@ -1068,6 +1103,14 @@
 % 
 %
 %    \begin{macrocode}
+\keys_define:nn { groupthm }
+  {
+    cache              .bool_set:N    = \g_@@_cache_bool,
+    cache              .default:n     = { true },
+    __cache version__  .int_set:N     = \g_@@_cache_version_document_int,
+    cache version      .meta:nn       = { groupthm } { cache = true, __cache version__ = #1 },
+    cache version      .default:n     = { 0 },
+  }
 \keys_define:nn { groupthm / theorem ~ group }
   {
     prefix      .tl_set:N      = \l_@@_key_prefix_tl,
@@ -1119,6 +1162,13 @@
 %    \end{macrocode}
 % 
 % 
+% 
+% Process package options:
+%    \begin{macrocode}
+\ProcessKeysOptions { groupthm }
+%    \end{macrocode}
+% 
+%
 % The only key whose default requires such handling is the \enquote{\texttt{name}} key,
 % which will be set to a capitalized version of the environment name
 % when not specified.
@@ -1918,11 +1968,13 @@
 %
 %   We also provide the three default groups:
 % 
+% \begin{variable}{all, starred, unnumbered}
 %    \begin{macrocode}
 \groupthm_new_group:nnnnn { all        } { } { } { } {               }
 \groupthm_new_group:nnnnn { starred    } { } { } { } { numbered = no }
 \groupthm_new_group:nnnnn { unnumbered } { } { } { } { numbered = no }
 %    \end{macrocode}
+% \end{variable}
 % 
 % \subsection{Iterating over powersets}
 % For generating the different variants of a theorem family,
@@ -2224,10 +2276,27 @@
   { \@@_Declarator: GroupedTheorem }
   { s O{} m }
   {
-    \use:c { groupthm_#1_theorem:nnn }
+    \bool_if:nTF
+      {
+        \g_@@_cache_bool
+        &&
+        \int_compare_p:n
+          {
+            \g_@@_cache_version_aux_int < \g_@@_cache_version_document_int
+          }
+      }
+      {
+        \hook_gput_code:nnn {@@/lazy} { groupthm }
+      }
+      {
+        \use:n
+      }
+    {
+      \use:c { groupthm_#1_theorem:nnn }
       { ##2 }
       { ##3 }
       { ##1 }
+    }
   }
 %    \end{macrocode}
 % \end{macro}
@@ -2589,6 +2658,9 @@
 %
 %
 %
+% \subsection{Caching}
+% 
+% 
 % 
 %    \begin{macrocode}
 %</package>