* “start” and “length.” “length” is optional and defaults to “the rest of the
* string.” “start” starts at {@code 0} and can be negative to denote starting
* at the end of the string.
* “start” and “length.” “length” is optional and defaults to “the rest of the
* string.” “start” starts at {@code 0} and can be negative to denote starting
* at the end of the string.