Re: How to determine buffer change

[Thorsten Jolitz]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Thorsten Jolitz <tjolitz@gmail.com>
>> Date: Sat, 05 Apr 2014 13:41:41 +0200
>> 
>> in a program I insert text in an empty temporary edit-buffer, what of
>> course modifies the `buffer-undo-list'.
>> Assume that at this moment (lets call it time T1)
>> 
>> ,------------------------------
>> | M-: (length buffer-undo-list)
>> `------------------------------
>> 
>> returns 9. 
>> 
>> Now when there are changes to the text in the edit-buffer, these are
>> copied to the original buffer after quitting. But when nothing has
>> changed after the insertion of the original text, it would be better to
>> simply discard the edit-buffer and not touch the original buffer at
>> all. 
>> 
>> I could remember the length of the buffer-undo-list at time T1 and then
>> check if it changed when quitting, but this does not seem very robust,
>> since this length grows and shrinks in both directions.
>
> Did you try using buffer-modified-tick?

Thats it probably, thanks.

Still have to figure out when to store the ticks - although I think I
set them directly after edit-buffer setup and directly before
edit-buffer quitting, the tick values differ quite a lot although no
editing took place, e.g.:

,---------------------
| tick1: 48 tick2: 97
| tick1: 76 tick2: 229
`---------------------

-- 
cheers,
Thorsten