[sf-perl] The SF Perl Raku Study Group, 03/28 at 1pm PDT

[Tiejun Li]

 For both of you, Joseph and Yary,
I filed a police report at Milpitas Police Department because of harassment. Please feel free to check it out.

TJ


    On Monday, March 29, 2021, 11:37:29 PM GMT+8, yary <not.com at gmail.com> wrote:  
 
 Hi Joe & other Raku study group attendees,
At the time I left, we were looking at a grammar with a speed-memory issue on large-ish files. I had a germ of an idea which I couldn't express, and from the meeting notes I see you have a simple fix "by changing stuff regex (.\*?) to non-greedy (.\*)" I suspect the greedy-optimization works because the thing after the "stuff" regex is near the end of the file. Thus if instead it was close to the beginning, it would have a similar issue with greedy and non-greedy would fix.
With a night to sleep on it, the thing I was thinking & trying to say is that, in the specialized HTML-grammar you had, the decision points are all at left-brackets. By re-writing "stuff" so that it will only backtrack when it hits a bracket, I expect more speed-memory gains.
How well does this perform vs the simple .* greedy fix?
    regex stuff    { (  # capture stuff (positional capture might not be needed)        [               # Stuff is a group of either            \<          # a left-bracket decision point          ||            # or            <-[ \< ]>+: # a ratcheting string of non-decision points        ]*              # 0-many of those. Greedy or non-greedy both work?    ) }  # end capture, end regex
This was harder to express verbally & in code than I expected!
-y


On Sun, Mar 28, 2021 at 4:23 PM Joseph Brenner <doomvox at gmail.com> wrote:

I did send this one out, but it doesn't seem that it went out exactly,
so let's try this one more time.   The Study Group is happening,
already in progress, though we'll be taking a break next week and
broadcasting a burning yule log with the soundtrack to Jesus Christ
Superstar.  (Just kidding)


Flaming Carrot, "Night Patrol" (1986) by Bob Burden:

    I feel it rising now...
    ... like little bubbles...
    THE MOON IS FULL...
    ... in a full moon, your brain floats to top of your head...
    I feel it...
    beginning to boil...
    a lot will happen tonight.

The Raku Study Group

March 28, 2021  1pm in California, 8pm in the UK

Zoom meeting link:
  https://us02web.zoom.us/j/81127128506?pwd=N0I5bkxUZTRLaWwxN2RJTGlsT254QT09

Passcode: 4RakuRoll

RSVPs are useful, though not needed:
  https://www.meetup.com/San-Francisco-Perl/events/277163968/
_______________________________________________
SanFrancisco-pm mailing list
SanFrancisco-pm at pm.org
https://mail.pm.org/mailman/listinfo/sanfrancisco-pm

_______________________________________________
SanFrancisco-pm mailing list
SanFrancisco-pm at pm.org
https://mail.pm.org/mailman/listinfo/sanfrancisco-pm
  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.pm.org/pipermail/sanfrancisco-pm/attachments/20210329/92a4aadf/attachment.html>