function sortedUniq(array) {
      return (array && array.length)
        ? baseSortedUniq(array)
        : [];
    }
This method is like `_.uniq` except that it's designed and optimized
for sorted arrays.

@static
@memberOf _
@since 4.0.0
@category Array
@param {Array} array The array to inspect.
@returns {Array} Returns the new duplicate free array.
@example

_.sortedUniq([1, 1, 2]);
// => [1, 2]