generate-manpage.nix: Make more readable

doc/manual/generate-manpage.nix

@@ -7,6 +7,7 @@ let
 
  showCommand = { command, details, filename, toplevel }:
  let
+
  result = ''
  > **Warning** \
  > This program is **experimental** and its interface is subject to change.
@@ -25,40 +26,51 @@ let
 
  ${maybeOptions}
  '';
+
  showSynopsis = command: args:
  let
  showArgument = arg: "*${arg.label}*" + (if arg ? arity then "" else "...");
  arguments = concatStringsSep " " (map showArgument args);
  in ''
  `${command}` [*option*...] ${arguments}
  '';
+
  maybeSubcommands = if details ? commands && details.commands != {}
  then ''
  where *subcommand* is one of the following:
 
  ${subcommands}
  ''
  else "";
+
  subcommands = if length categories > 1
  then listCategories
  else listSubcommands details.commands;
+
  categories = sort (x: y: x.id < y.id) (unique (map (cmd: cmd.category) (attrValues details.commands)));
+
  listCategories = concatStrings (map showCategory categories);
+
  showCategory = cat: ''
  **${toString cat.description}:**
 
  ${listSubcommands (filterAttrs (n: v: v.category == cat) details.commands)}
  '';
+
  listSubcommands = cmds: concatStrings (attrValues (mapAttrs showSubcommand cmds));
+
  showSubcommand = name: subcmd: ''
  * [`${command} ${name}`](./${appendName filename name}.md) - ${subcmd.description}
  '';
+
  maybeDocumentation = if details ? doc then details.doc else "";
+
  maybeOptions = if details.flags == {} then "" else ''
  # Options
 
  ${showOptions details.flags toplevel.flags}
  '';
+
  showOptions = options: commonOptions:
  let
  allOptions = options // commonOptions;
@@ -99,7 +111,7 @@ let
  in [ cmd ] ++ concatMap subcommand (attrNames details.commands or {});
 
  parsedToplevel = builtins.fromJSON toplevel;
- 
+
  manpages = processCommand {
  command = "nix";
  details = parsedToplevel;