use strict;

my $line = "http://127.0.0.1/home_dir";

if ($line =~ /     # begin regex
         (         # begin Capture #1
         http:       # protocol
         )           # end Capture #1
         \/+          # (discard) one (or more) forward slashes; imprecise
         (127\.0\.0\.1)    # Capture #2, including the dots IP
         \/              # (discard) one forward slash
         (home_dir)       # Capture #3 (literal and simplistic)
         /x)           # end regex, use extended syntax, end the if predicate

      {
            print "$1\n";
            print "$2\n";
            print "$3\n";
            }
            else
            {
            print "Bad RegEx\n";
      }
exit;