docs: function rollback() {
      var parsed = ensureConfig();
      var name = parsed.name;
      // check if is an index number.
      // if yes try to lookup the id
      // by its index.
      try {
          var idx = void 0;
          if (/^[0-9]+$/.test(name)) {
              idx = parseInt(parsed.name) - 1;
              if (idx >= 0) {
                  var keys = Object.keys(mu.rollbacks);
                  var key = keys[idx];
                  if (key)
                      name = key;
              }
          }
      }
      catch (ex) { }
      mu.rollback(parsed.name, parsed.output);
  }