if (/[\x20]{5}\(base 16\)[\t]{2}/) {
...
  if ($_ =~ m/([\d]+\.[\d]+\.[\d]+\.[\d]+).*([\w]{4})\.([\w]{4})\.([\w
+]{4})/i) {

[download]

Why put a character class inside a character class? 

  if (/\x20{5}\(base 16\)\t{2}/) {
...
  if ($_ =~ m/(\d+\.\d+\.\d+\.\d+).*(\w{4})\.(\w{4})\.(\w{4})/i) {

[download]

And why use the /i option on a pattern that contains NO literal alphabetic characters? 



open(INPUT, $ARGV[0]) || die "Cannot do eet! $!";      # Takes the inp
+ut file name on the command line and builds an array.
while (<INPUT>) {                                    # This is the ARP
+ Cache file created from a copy/paste of a routers 
  push @data, "$_";                                    # show arp comm
+and.
}
close(INPUT);
                                                    
for (@data) {     # This section iterates over the ARP cache array and
+ pulls the IP and MAC address out and stores it into a hash
  if ($_ =~ m/([\d]+\.[\d]+\.[\d]+\.[\d]+).*([\w]{4})\.([\w]{4})\.([\w
+]{4})/i) {            # Key is MAC 
    my $temp = $2.$3.$4;                                              
+                      # Value is IP
    $hash{$temp} = $1;
  }
}

[download]

What is the point of  @data?    Why not just populate  %hash from inside the while loop?    And why copy  $_ to a string before pushing it into  @data?



In reply to Re: Regex matching part of one hash key to another by jwkrahn
in thread Regex matching part of one hash key to another by KevinNC

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