passing negative value to extract characters backwards in set method

Hello, when i try to cursor the end position, `$('input[name="example"]').textrange('set', -1);` could not run as it should be, so i add some lines. Now, i can extract characters from the end of the string using a negative number. 
Besides, I'm sorry to have `set` wiki page edited. i'm new here and have no idea to revert it yet. Apology :-P