Need help with regex

[StickyBit]

Folks,

I need to filter the following string from a file:

P9PF-JKUK-KLJI-KLNH-BHFT-MKNB-P (the string appears by itself on a line)

I'm using the following regex: if (/^\w{4}\-/) that does work but it needs fine tuning because I sometimes pick up garbage like the following:

font-family:Arial'><o>&nbsp;</o></span></font></p>

MIME-Version: 1.09133

I’m trying to use a regex that will find a string containing 4 alphanumeric characters followed by a dash '-' then 4 more alphanumeric characters etc. Can anyone help me?

thx.

 

[columb]

Hw well defined is your string?
could

/^\w{4}\-\w{4}\-\w{4}\-\w{4}\-\w{4}\-\w{4}\-\w$/

closely defines your pattern ( and will therefore reject your example of false positives

 

[duncdude]

[b]#!/usr/bin/perl[/b]

undef $/;

$_ = <DATA>;

s|^[A-Z0-9]{3}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{1}\n||m;

print;

[blue]__DATA__
blah
blah blah
9PF-JKUK-KLJI-KLNH-BHFT-MKNB-P
blah blah
blah[/blue]

Kind Regards
Duncan

 

[StickyBit]

Thanks guys!

 

[duncdude]

no problem dude


Kind Regards
Duncan

 

[mikevh]

Another suggestion:

#!perl
use strict;
use warnings;

/^([A-Z0-9]{4}-){6}[A-Z0-9]$/ && print while <DATA>;

__DATA__
blah
blah blah
P9PF-JKUK-KLJI-KLNH-BHFT-MKNB-P
blah blah
blah

Re is "4 alphanumeric chars followed by a dash, repeated 6 times, followed by one alphanumeric char".
Dunc, you changed line 3 of the data slightly.
(Left off the first char, so your re's a little different.)

 

[duncdude]

Mike

You got me again!

Lucky someone's got their eye on me... (someone who knows their onions fortuntately!)

Thanks dude!

You've also - by omission - kindly pointed out that my regex could have been reduced to:-

[tt]s|[A-Z0-9]{3}-([A-Z0-9]{4}-){5}[A-Z0-9]\n||;[/tt]


... but now it does not work with the beginning of line caret? weird!

Cheers


Kind Regards
Duncan

 

[mikevh]

Dunc, you need the /m modifier on the end of your re for it to work. With /m, ^ matches at the beginning of a line, anywhere within the multi-line string. Without /m, ^ matches only at the beginning of the entire string. Your modified re works if you use /m.

Trying out your code, I see we had different interpretations of StickBit's request to "filter the following string from a file": your idea of "filtering" was to remove the string; my idea was to return it. Both valid interpretations, given what info we had.

 

[duncdude]

thank you - it's always good to learn another trick! gotta keep learning those regex's - an awesomely powerful tool i'm sure you'll agree

and I agree - filter is a bit ambiguous - but again I think you're being modest... he mentioned that he was [red]finding[/red] other [red]rubbish[/red] - so I guess your regex that returned the match is correct


Kind Regards
Duncan

 

[StickyBit]

I guess filter was a little ambiguous; I should have used the word extract.

Thanks again.

StickyBit.