PERL Pattern Matching

[pbatt]

Hello,

I'm searching through a generated file of HTML code and am trying to abstract a date. Basically, I begin by encapsulating a small portion of the file using 'until' knowing that there are 2 strings guarenteed to be there.

The date is of the format 2005-09-21 07:45:19.0

Can anyone help with a way to search for this date, then assign it to a variable? I tried using /-- ::./ but that doesn't match?

Thanks!

 

[TrojanWarBlade]

/(\d\d\d\d-\d\d-\d\d\s+\d\d:\d\d:\d\d\.\d)/

S1 will hold the matched string.


Trojan.

 

[pbatt]

Ok, the string match makes clear sense, but what do you mean when you refer to S1?

Thank you!

 

[TrojanWarBlade]

Sorry, $1 (dollar 1)
It's the scalar that the resultant match will be stored in (due to the parentheses).


Trojan.

 

[rharsh]

I think he meant $1.

 

[pbatt]

Does this make sense, I'm a little confused on how to assign the pattern match:

$_ = /(\d\d\d\d-\d\d-\d\d\s+\d\d:\d\d:\d\d\.\d)/;
print "$_\n";

Or should I add the /(\d\d.....)/ to an 'if' statement, and print $1?

 

[TrojanWarBlade]

Yep rhash, I meant $1.
pbatt,
Assuming your string is in $_ you just need to:

/(\d\d\d\d-\d\d-\d\d\s+\d\d:\d\d:\d\d\.\d)/;
print "[red]$1[/red]\n";

Trojan.

 

[TrojanWarBlade]

Better though would be to;

/(\d\d\d\d-\d\d-\d\d\s+\d\d:\d\d:\d\d\.\d)/
and print "$1\n";

So as to only print $1 if the match succeeds.


Trojan.

 

[pbatt]

By default m// will search in $_, right?

When I use that, I get a "Use of uninitialized value in concatenation (.) or string at..."

Do you know what this means?

 

[pbatt]

Ok, got it working. Still getting a "Use of uninitialized value in pattern match at line..." Had to add an extra -\d\d since there is a date and month field.

I'll ignore that error since I'm getting the result I want, is that bad?

Thank you very much for your help!

 

[TrojanWarBlade]

The "Use of uninitialized value in pattern match at line..." means that sometimes "$_" is undefined. If it's undefined then it's very empty indeed so I guess you'll get away with that!
Still, you might do well to find out why your $_ is sometimes undefined.


Trojan.

 

[pbatt]

Ok, I'll check it out.

Thanks again for the help!