code: function (fn) {
              var requires = [];
              // Remove comments from the callback string,
              // look for require calls, and pull them into the dependencies,
              // but only if there are function args.
              fn.toString()
                  .replace(commentRegExp, '')
                  .replace(requireRegExp, function (match, _, dep) {
                      requires.push(dep);
                  });
              return requires;
          }
docs: ---------------------------------- for modules