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Perl Meta character understanding

 
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# 1  
Old 08-17-2010
Perl Meta character understanding
Hello All,

I have some expression:

Code:
if (/^([12]\d\d\d[01]\d[0-3]\d\.\d\d\d\d\d\d)\s+(.+)$/) 
{
    warn "$argv0(" . __LINE__ . "): rbl2ts{$2} == '$rbl2ts{$2}' \$1==$1\n" if       ($debug);
    $rbl2ts{$2} = $1 if (!defined($rbl2ts{$2}) or ($1 le $rbl2ts{$2}));
   warn "$argv0(" . __LINE__ . "): rbl2ts{$2} == '$rbl2ts{$2}' \$1==$1\n\n" if ($debug);
}


Can Anyone make me understand how this if condition will get satisfy....
mean what is the condition basically
# 2  
Old 08-17-2010
Any of the following would match.

Code:
^ = beginning of sting
[01] = this spot can be 0 or 1
[0-3] = this spot can be 0, 1, 2 or 3
\d = Numeric
\. = means a .
\s+ = 1 or more white space (tab or space)
$ = end of string
.+ = 1 or more of any character

the rest appears to give specifics of errors or debug info. $rb12ts{$2} is application specific so its hard to tell.

Code:
   10000000.000000 Somthing here it doesnt care about
   10000010.000000 Somthing here it doesnt care about
   10000020.000000 Somthing here it doesnt care about
   10000030.000000 Somthing here it doesnt care about
   20000000.000000 Somthing here it doesnt care about
   20000010.000000 Somthing here it doesnt care about
   20000020.000000 Somthing here it doesnt care about
   20000030.000000 Somthing here it doesnt care about
   10001000.000000 Somthing here it doesnt care about
   10001010.000000 Somthing here it doesnt care about
   10001020.000000 Somthing here it doesnt care about
   10001030.000000 Somthing here it doesnt care about
   20001000.000000 Somthing here it doesnt care about
   20001010.000000 Somthing here it doesnt care about
   20001020.000000 Somthing here it doesnt care about
   20001030.000000 Somthing here it doesnt care about
   29991939.999999 Somthing here it doesnt care about

# 3  
Old 08-17-2010
Thanks.....
I got a good information how to deal with this meta character.....

one more question:

Code:
if (m/^([0-3]\d-[a-z][a-z][a-z]-\d\d\.\d\d:\d\d:\d\d)\s+(\S+)\s+\S+\s+"(\S+)"/oi)

Here what is the meaning of :\d : any specific meaning or just :numeric...

and what is oi and "(\S+)"
# 4  
Old 08-17-2010
\S = Not White Space
+ = 1 or more

Not sure about o but i is case-insensitive
 
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