docs: function pickBy(fn, moments) {
          var res, i;
          if (moments.length === 1 && isArray(moments[0])) {
              moments = moments[0];
          }
          if (!moments.length) {
              return moment();
          }
          res = moments[0];
          for (i = 1; i < moments.length; ++i) {
              if (moments[i][fn](res)) {
                  res = moments[i];
              }
          }
          return res;
      }