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in reply to Re^2: Regexp: Private IP Addresses
in thread Regexp: Private IP Addresses

Yes, using a regular expression is "much more efficient", but yours is in some cases, as you point out, incorrect. And using Net::IP::Match::Regexp you can still do more than sixty seven thousand comparisons per second (on my old and rusty laptop, anyway) if the regexp is initialized once only. So what do you want:
$ cat 791149.pl use strict; use warnings; use Net::IP::Match::Regexp qw( create_iprange_regexp match_ip ); use Benchmark qw / cmpthese /; my $regexp_init_once = create_iprange_regexp( qw( 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 ) + ); sub netip { my $regexp = create_iprange_regexp( qw( 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 + ) ); return ( match_ip( $_[0], $regexp ) ); } sub netip_init_once { return match_ip( $_[0], $regexp_init_once ); } sub regexp { return $_[0] =~ /^(10\.\d+|172\.(1[6-9]|2\d|3[0-1])|192\.168)(\.\d+) +{2}$/; } cmpthese( -1, { 'netip' => sub { netip('1.2.3.4') }, 'netip_init_once' => sub { netip_init_once('1.2.3.4') }, 'regexp' => sub { regexp('1.2.3.4') }, } ); __END__ $ perl 791149.pl Rate netip netip_init_once reg +exp netip 2438/s -- -96% -1 +00% netip_init_once 67622/s 2674% -- - +95% regexp 1390157/s 56918% 1956% + --
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