Beefy Boxes and Bandwidth Generously Provided by pair Networks
go ahead... be a heretic
 
PerlMonks  

Re^3: grep trouble

by davido (Archbishop)
on Apr 17, 2011 at 16:08 UTC ( #899822=note: print w/ replies, xml ) Need Help??


in reply to Re^2: grep trouble
in thread grep trouble

It could be a convenience for a switch with fall-through, or along similar (but more oddball lines), possibly an implementation of Duff's Device.


Dave


Comment on Re^3: grep trouble
Re^4: grep trouble (body of flip-flop range)
by LanX (Canon) on Apr 17, 2011 at 16:21 UTC
    Thanks!

    IMHO sounds like far less than 1‰ of all CPAN modules might rely on this.


    UPDATE:

    OK found another use-case, I just recently had the need in my ORG-Parser to distinguish the range delimiters and the range "body" with a flip-flop-operator, like for ORG's "BEGIN/END"-blocks.

    This can be simplified (i.e. more DRY), if one has access to the last successful pattern:

    DB<114> for(0..99) {print if (/10/../20/ and not //)} 111213141516171819 DB<115> for(0..99) {print if (/10/../20/)} 1011121314151617181920 DB<116> for(0..99) {print if (/10/../20/ and //)} 1020

    I think that's a more frequent application, I even slightly remember seeing it in Friedl's book.

    But I'd rather prefer an explicit special varą, something like $PATTERN or $&& (in analogy to $MATCH resp. $&) .

    Cheers Rolf

    1) an special var has the advantage that the regex itself can be accessed, e.g. printed.

    update

    for limitations see update in Re^2: Extract table from a block of text (updated)

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://899822]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (3)
As of 2015-07-05 23:54 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (68 votes), past polls