reverse

Reverses the contents of this string builder and returns this instance.

Surrogate pairs included in this string builder are treated as single characters. Therefore, the order of the high-low surrogates is never reversed.

Note that the reverse operation may produce new surrogate pairs that were unpaired low-surrogates and high-surrogates before the operation. For example, reversing "\uDC00\uD800" produces "\uD800\uDC00" which is a valid surrogate pair.