nix store --help: Include store type documentation

doc/manual/generate-manpage.nix

@@ -1,4 +1,4 @@
-{ toplevel }:
+cliDumpStr:
 
 with builtins;
 with import ./utils.nix;
@@ -63,7 +63,10 @@ let
         * [`${command} ${name}`](./${appendName filename name}.md) - ${subcmd.description}
       '';
 
-      maybeDocumentation = if details ? doc then details.doc else "";
+      maybeDocumentation =
+        if details ? doc
+        then replaceStrings ["@stores@"] [storeDocs] details.doc
+        else "";
 
       maybeOptions = if details.flags == {} then "" else ''
         # Options
@@ -110,13 +113,13 @@ let
       };
     in [ cmd ] ++ concatMap subcommand (attrNames details.commands or {});
 
-  parsedToplevel = builtins.fromJSON toplevel;
+  cliDump = builtins.fromJSON cliDumpStr;
 
   manpages = processCommand {
     command = "nix";
-    details = parsedToplevel;
+    details = cliDump.args;
     filename = "nix";
-    toplevel = parsedToplevel;
+    toplevel = cliDump.args;
   };
 
   tableOfContents = let
@@ -124,4 +127,14 @@ let
       "    - [${page.command}](command-ref/new-cli/${page.name})";
     in concatStringsSep "\n" (map showEntry manpages) + "\n";
 
+  storeDocs =
+    let
+      showStore = name: { settings }:
+        ''
+          ## ${name}
+
+          ${showSettings false settings}
+        '';
+    in concatStrings (attrValues (mapAttrs showStore cliDump.stores));
+
 in (listToAttrs manpages) // { "SUMMARY.md" = tableOfContents; }