Idempotence of null operations

[countvajhula]

Certain commands insert extra characters that are useful and commonly desired when making changes. But if the command was executed accidentally or if the user changed their mind, we want to ensure that canceling the command restores the buffer to its original state. This ensures that null commands are idempotent, providing a more cohesive experience. The following commands should be reviewed in this connection:

(I)nsert-before
(A)ppend-after
(w)rap
(W)rap

and possibly even:
(o)pen-below
(O)pen-above
(c)hange
(C)hange-remaining
(s)ubstitute (i.e. replace)