But I was matching against  (\d*) \z which cannot fail, although it could match an empty string of digits — which can be useful in and of itself!

Update: Interestingly, what is captured | assigned to  $var in a statement like
    my ($var) = $s =~ m{ (\d+) \z }xms;
is not the same as what is captured to | not necessarily the same as the value of $1: 

c:\@Work\Perl\monks>perl -wMstrict -le
"'zot' =~ m{ (zot) }xms;
 ;;
 for my $s (
   'http://172.20.37.115:8080/se/1.0/pro/subs/198968/',
   'http://172.20.37.115.8080/se/1.0/pro/123456',
   ) {
   my ($var) = $s =~ m{ (\d+) \z }xms;
   print '$var is ', defined($var) ? '' : 'UN', 'defined';
   print qq{'$s' -> '$var' (\$1 is '$1')};
   }
"
$var is UNdefined
Use of uninitialized value $var in concatenation (.) or string at -e l
+ine 1.
'http://172.20.37.115:8080/se/1.0/pro/subs/198968/' -> '' ($1 is 'zot'
+)
$var is defined
'http://172.20.37.115.8080/se/1.0/pro/123456' -> '123456' ($1 is '1234
+56')

[download]
This warrants a bit more research!

Give a man a fish:  <%-(-(-(-<

In reply to Re^3: how to find particular string and store in to variable by AnomalousMonk
in thread how to find particular string and store in to variable by bhushanQA

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