 |  |  |  |  |  |  |  |
number of regex match
Please support our Perl advertiser: Programming Forums - DaniWeb Sister Site
 |
hi,
i'd like to know how to get the number of regexp matches a pattern returns
ex: if I have $_ = "fooFOObarBAR";$_ =~ /[a-z]/
it would return 6
thx
SNIP
i'd like to know how to get the number of regexp matches a pattern returns
ex: if I have $_ = "fooFOObarBAR";$_ =~ /[a-z]/
it would return 6
thx
SNIP
Last edited by happygeek; Jan 15th, 2009 at 7:31 pm. Reason: email snipped
•
•
Join Date: Feb 2009
Posts: 58
Reputation: 
Solved Threads: 2
Junior Poster in Training
Perl Syntax (Toggle Plain Text)
•
•
Join Date: Feb 2009
Posts: 58
Reputation:
Solved Threads: 2
Junior Poster in Training
But you have to remove the second $_, that is resetting the value.
Perl Syntax (Toggle Plain Text)
•
•
Join Date: Dec 2004
Posts: 2,413
Reputation:
Solved Threads: 211
Try not to back to back post... it's bad etiquette (though sometimes necessary). The better alternative is to edit your post within the grace-period provided by the site.
Last edited by Comatose; Feb 5th, 2009 at 11:03 am.
•
•
Join Date: Feb 2009
Posts: 58
Reputation:
Solved Threads: 2
Junior Poster in Training
OK, will do. Sorry. I am new to these forums, but not new to perl. I will edit in the future. My bad.
•
•
Join Date: Mar 2006
Posts: 898
Reputation:
Solved Threads: 67
Practically a Posting Shark
An interesting construct to do the same thing. No need to actually use a named array:
But I would do it like this myself:
Perl Syntax (Toggle Plain Text)
But I would do it like this myself:
Perl Syntax (Toggle Plain Text)
•
•
Join Date: Feb 2009
Posts: 58
Reputation:
Solved Threads: 2
Junior Poster in Training
Well, I would normally have left the named array off and just done it with a simple scalar, but since the questioner is a newbie to perl, I wanted to show where the values end up when you use () and when you use just a scalar. I read a funny article in perl journal years ago (it was satire) in which the guy was supposedly using perl for military technology and forgot the () in the tolerances, so he was getting a "1" because it was the count of matches, rather than the value of matches.
•
•
Join Date: Mar 2006
Posts: 898
Reputation:
Solved Threads: 67
Practically a Posting Shark
Cool. Its sort of moot anyway in this example since tr/// is really the better way to do it since it involves no pattern matching, just simple character recognition.
I just thought the construct was interesting:
$count = () = /[a-z]/g;
I remember the first time I saw that years ago and it was a bit of a revelation in how perl works.
I just thought the construct was interesting:
$count = () = /[a-z]/g;
I remember the first time I saw that years ago and it was a bit of a revelation in how perl works.
•
•
Join Date: Feb 2009
Posts: 58
Reputation:
Solved Threads: 2
Junior Poster in Training
Yeah, I find that interesting as well. Perl is amazing - thanks Larry!
I told a co-worker that I use perl everyday and he said "I hate that language" so I immediately lost all respect for him (haha).
You're right tr/// is better and more efficient. I sometimes use some old tricks because I have never had anyone actually teach me perl, just figured out by doing. I am now writing (most) everything object oriented in perl - which I hadn't before because I wrote most stuff very C-like.
I told a co-worker that I use perl everyday and he said "I hate that language" so I immediately lost all respect for him (haha).
You're right tr/// is better and more efficient. I sometimes use some old tricks because I have never had anyone actually teach me perl, just figured out by doing. I am now writing (most) everything object oriented in perl - which I hadn't before because I wrote most stuff very C-like.
•
•
Join Date: Mar 2006
Posts: 898
Reputation:
Solved Threads: 67
Practically a Posting Shark
Well, we are in the same boat, I never learned perl formally either. Last time i was in school I was learning how to write programs on punch cards. Which totally turned me off to programming for a very long time. 
Last edited by KevinADC; Feb 5th, 2009 at 2:00 pm.
|
Similar Threads
- Basic Perl Web Upload Script (Perl)
- Regular Expressions with Decimal Points (Java)
- Need sample code for Text File Compression!!! (C++)
- Regex matches all but specific word? (Perl)
- rootmap help??urgent plz.. (PHP)
- Attribute error, Cookies not found! (Python)
- how to read csv file without using StringTokenizer (Java)
- Need help making simple random images (PHP)
- Trim Strings (JavaScript / DHTML / AJAX)
- Regular Expressions (C#)
Other Threads in the Perl Forum
- Previous Thread: Reading Substring from a string
- Next Thread: match data with another value in another file
| Thread Tools | Search this Thread |
Latest Perl Posts
- Today's Posts
- Unanswered Threads
Related Forum Features
Tag cloud for Perl
