I am in a situation on Meta Stack Overflow in which I dispute the validity of the system notification text "Code in your answer has been edited", because there was no code in the answer before the edit; merely, code was added to the answer after the edit.
Another user claims that this is simply a "more vague" meaning of "edit":
Saying it was edited is not wrong, it's just more vague. [..] I'm asserting that your definition of "edited" is incorrectly narrow.
I'm fairly confident, though, that in the phrase "to edit X" the "X" is what was present before the edit, not as a result of it. That is, you cannot edit something that is not there by adding the thing.
However I'm struggling to find a way to prove it.
How may I prove the following in a semi-formal manner?
"Hi there." => "Hi you." # "I edited the second word". <-- OK
"Hi there." => "Hi there you." # "I edited the third word". <-- NOT OK