#!perl

use strict;
use warnings;

my $myfetch = 'http:\\myurlinfo\mypage.html';
$myfetch =~ m!([^/!]*$)! ?
   print $1 :
   print 'Whoops...';
__END__
Unmatched [ in regex; marked by <-- HERE in m/([ <-- HERE ^// at (eval
+ 1) line 7.
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Probably you meant

#!perl

use strict;
use warnings;

my $myfetch = 'http:\\myurlinfo\mypage.html';
$myfetch =~ m!([^\\]+)$! ?
   print $1 :
   print 'Whoops...';
__END__
mypage.html
[download]

Cheers,
CombatSquirrel.