anchor.diff:                 + "[`${command} ${name}`](./${appendName filename name}.md)"
                  + " - ${cmds.${name}.description}\n")
                  (attrNames cmds));
  -         in
  -         "where *subcommand* is one of the following:\n\n"
  +         in ''
  +         where *subcommand* is one of the following:
  +
  +         ''
            # FIXME: group by category
            + (if length categories > 1
               then
  
positive.code:   showCommand =
      { command, def, filename }:
      ''
        **Warning**: This program is **experimental** and its interface is subject to change.
      ''
      + "# Name\n\n"
      + "`${command}` - ${def.description}\n\n"
      + "# Synopsis\n\n"
      + showSynopsis { inherit command; args = def.args; }
      + (if def.commands or {} != {}
         then
           let
  
negative.code:   showSynopsis =
      { command, args }:
      "`${command}` [*option*...] ${concatStringsSep " "
        (map (arg: "*${arg.label}*" + (if arg ? arity then "" else "...")) args)}";
  
    processCommand = { command, def, filename }:
      [ { name = filename + ".md"; value = showCommand { inherit command def filename; }; inherit command; } ]
  