vendors/tempy.js/rethrow
    function rethrow() {
      var callback;
      if (DEBUG) {
        var backtrace = new Error();
        callback = debugCallback;
      } else
        callback = missingCallback;
      return callback;
      function debugCallback(err) {
        if (err) {
          backtrace.message = err.message;
          err = backtrace;
          missingCallback(err);
        }
      }
      function missingCallback(err) {
        if (err) {
          if (process.throwDeprecation)
            throw err;
          else if (!process.noDeprecation) {
            var msg = "fs: missing callback " + (err.stack || err.message);
            if (process.traceDeprecation)
              console.trace(msg);
            else
              console.error(msg);
          }
        }
      }
    }