[cl-ppcre-devel] Buffered multi-line question

[Sébastien Saint-Sevin]

> > Throw & Catch, of course.  I'm just not very familiar with this kind
> > of big jumps.  I should !!!!
>
> BTW, I don't know if these were just examples or if they're actually
> related to your real problem but in this specific case there's
> certainly room for improvement:
>
>   CL-USER> (defvar *my-string* "line1 word1 word2
>   line2 word1 word2
>   line3 word1 word2")
>   *MY-STRING*
>   CL-USER> (let ((end-of-first-line 17))
>                    (defun my-filter (pos)
>                       (format t "Called at: ~A~%" pos)
>                       (cond ((< pos end-of-first-line)
>                               pos)
>                             (t
>                               (throw 'stop-it nil)))))
>   MY-FILTER
>   CL-USER> (defvar *my-scanner*
>                    '(:sequence
>                       (:filter my-filter 0)
>                       :word-boundary
>                       "line2"
>                       (:greedy-repetition 1 nil :word-char-class)
>                       :word-boundary))
>   *MY-SCANNER*
>   CL-USER> (catch 'stop-it
>              (scan *my-scanner* *my-string*))
>   Called at: 0
>   Called at: 1
>   Called at: 2
>   Called at: 3
>   Called at: 4
>   Called at: 5
>   Called at: 6
>   Called at: 7
>   Called at: 8
>   Called at: 9
>   Called at: 10
>   Called at: 11
>   Called at: 12
>   Called at: 13
>   Called at: 14
>   Called at: 15
>   Called at: 16
>   Called at: 17
>   NIL
>   CL-USER> (setf *my-scanner*
>                  '(:sequence
>                     :multi-line-mode-p
>                     :start-anchor
>                     (:filter my-filter 0)
>                     :word-boundary
>                     "line2"
>                     (:greedy-repetition 1 nil :word-char-class)
>                     :word-boundary))
>   (:SEQUENCE :MULTI-LINE-MODE-P :START-ANCHOR (:FILTER MY-FILTER 0)
>    :WORD-BOUNDARY "line2" (:GREEDY-REPETITION 1 NIL :WORD-CHAR-CLASS)
>    :WORD-BOUNDARY)
>   CL-USER> (catch 'stop-it
>              (scan *my-scanner* *my-string*))
>   Called at: 0
>   Called at: 18
>   NIL
>
> Not sure if that's relevant, though.

It was just an example.
I chose "line2" as the first word that wasn't in line1 so that the match
fails.
Usually, I use as much anchors as I can in the regex coz it considerably
decrease the number of backtracking with quantifiers of all kind.

Cheers,
Sebastien.