Re: Discrepancy in definition/use of match-data?

[Stephen J. Turnbull]

>>>>> "rms" == Richard Stallman <address@hidden> writes:

        OK, I have tripped this in three functions so far.  All
    of them look relevant to GNU Emacs.

        isearch.el (isearch-repeat): both calls to match-{beginning,end}

    rms> It is checking whether the last match for the search string
    rms> was empty.  I think this change should make it work without
    rms> using the match-data.  Does it work?

Your change eliminates the match-data access, of course, but I just
realized as I tried to test it that I really don't have a feel for
what "work" means.  I don't use regexp-isearch very often, and regexps
that match the null string almost never.  As far as I can tell in a
few days testing string searching and the simple regexps that I
commonly use are producing no surprises, and "artificial" regexps that
should match the empty string do, while other matchers do not.  Repeat
regexp searches for ".*" behave the same with both implementations,
including wrapping around bob and eob.

So I would say it works.  Well enough to install in our beta tree,
anyway.

*** isearch.el  06 Jun 2004 09:56:16 -0400      1.228
--- isearch.el  18 Jun 2004 22:10:53 -0400      
***************
*** 999,1005 ****
  
    (if (equal isearch-string "")
        (setq isearch-success t)
!     (if (and isearch-success (equal (match-end 0) (match-beginning 0))
             (not isearch-just-started))
        ;; If repeating a search that found
        ;; an empty string, ensure we advance.
--- 999,1006 ----
  
    (if (equal isearch-string "")
        (setq isearch-success t)
!     (if (and isearch-success
!            (equal (point) isearch-other-end)
             (not isearch-just-started))
        ;; If repeating a search that found
        ;; an empty string, ensure we advance.


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