Re: A better UI than perform-replace (was: Rename refactoring, or something like that)

[Richard Stallman]

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  > - No good way to pause the replacement procedure.

You can do that easily by typing any ordinary editing
command, or ESC.  To resume, use C-x ESC ESC RET.

  > - No good way to undo a replacement.

Yes there is: type C-_ (C-- on an X terminal).

Nonethless, I can see how your new mode might be useful.  But the
*replace* buffer might also get in the way.

I think we should poll the users before changing the default behavior.
We could ask them to suggest changes in the new feature
as well as to say whether they want it as the default.

  > To re-describe things in a shorter way, *replace* should be a staging
  > area for the `perform-replace' operation.

I see a possible pitfall here.  It seems to envision finding all the
matches before operating on any of them.

Currently, if you pause and resume the query replace loop, it resumes
starting from point and it finds all matches in the current text after
point.  So if during he pause you edited something below, creating or
eliminating matches, it operates on the matches that exist after those
changes.

But if the list of matches was made in advance, it won't understand
that the buffer has changed.  It can double-check the old matches
to make sure they still match, but it will ignore newly introduced
matches.

-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.