How to undo/redo one letter a time.

[Guest]

I mean when I type 'SELECT', it highlights 'SELECT' with blue. When I press 'Undo', the letter 'T' disappears and 'SELEC' becomes black. I want it is like Microsoft Word: one press 'undo' one letter removed.
Thank you in advance.

[robert]

What do you mean when you say you "press Undo?" RSTA's default undo behavior is to remove all characters typed contiguously. This does mimic the behavior seen in Word pretty well. So typing "SELECT" and then pressing ctrl+Z (or right click -> Undo) will remove the entire word "SELECT". Are you seeing different behavior? If so, can you post a small sample program that demonstrates this behavior?