"->copy()" actually creates a new object when called.

my $ip = new NetAddr::IP::Lite '192.168.1.123';
print "$ip\n";

Will print the string 192.168.1.123/32.

my $ip = new6 NetAddr::IP::Lite '192.168.1.123';
print "$ip\n";

Will print the string 0:0:0:0:0:0:C0A8:17B/128

if (NetAddr::IP::Lite->new('127.0.0.1','255.0.0.0') eq '127.0.0.1/8')
   { print "Yes\n"; }

Will print out "Yes".

Comparison with "==" and "!=" requires both operands to be NetAddr::IP::Lite objects.

/24 > /16

Comparison should not be done on netaddr objects with different CIDR as this may produce indeterminate - unexpected results, rather the determination of which netblock is larger or smaller should be done by comparing

$ip1->masklen <=> $ip2->masklen

print NetAddr::IP::Lite->new('127.0.0.1/8') + 5;

will output 127.0.0.6/8. The address will wrap around at the broadcast back to the network address. This code:

print NetAddr::IP::Lite->new('10.0.0.1/24') + 255;

outputs 10.0.0.0/24.

Returns the the unchanged object when the constant is missing or out of range.

2147483647 <= constant >= -2147483648

Returns undef if the difference is out of range.

new6FFFF specifically returns an IPv4 address in IPv6 format according to RFC4291

new6               ::xxxx:xxxx
new6FFFF      ::FFFF:xxxx:xxxx

The third method "new_no" is exclusively for IPv4 addresses and filters improperly formatted dot quad strings for leading 0's that would normally be interpreted as octal format by NetAddr per the specifications for inet_aton.

new_from_aton takes a packed IPv4 address and assumes a /32 mask. This function replaces the DEPRECATED :aton functionality which is fundamentally broken.

The last two methods new_cis and new_cis6 differ from new and new6 only in that they except the common Cisco address notation for address/mask pairs with a space as a separator instead of a slash (/)

These methods are DEPRECATED because the functionality is now included in the other "new" methods

i.e.  ->new_cis('1.2.3.0 24')
      or
      ->new_cis6('::1.2.3.0 120')

"->new6" and "->new_cis6" mark the address as being in ipV6 address space even if the format would suggest otherwise.

i.e.  ->new6('1.2.3.4') will result in ::102:304
addresses submitted to ->new in ipV6 notation will
remain in that notation permanently. i.e.
      ->new('::1.2.3.4') will result in ::102:304
whereas new('1.2.3.4') would print out as 1.2.3.4
See "STRINGIFICATION" below.

$addr can be almost anything that can be resolved to an IP address in all the notations I have seen over time. It can optionally contain the mask in CIDR notation. If the OPTIONAL perl module Socket6 is available in the local library it will autoload and ipV6 host6 names will be resolved as well as ipV4 hostnames.

prefix notation is understood, with the limitation that the range specified by the prefix must match with a valid subnet.

Addresses in the same format returned by "inet_aton" or "gethostbyname" can also be understood, although no mask can be specified for them. The default is to not attempt to recognize this format, as it seems to be seldom used.

###### DEPRECATED, will be remove in version 5 ############ To accept addresses in that format, invoke the module as in

use NetAddr::IP::Lite ':aton'

###### USE new_from_aton instead ##########################

If called with no arguments, 'default' is assumed.

If called with an empty string as the argument, returns 'undef'

$addr can be any of the following and possibly more...

n.n
n.n/mm
n.n mm
n.n.n
n.n.n/mm
n.n.n mm
n.n.n.n
n.n.n.n/mm            32 bit cidr notation
n.n.n.n mm
n.n.n.n/m.m.m.m
n.n.n.n m.m.m.m
loopback, localhost, broadcast, any, default
x.x.x.x/host
0xABCDEF, 0b111111000101011110, (or a bcd number)
a netaddr as returned by 'inet_aton'

Any RFC1884 notation

::n.n.n.n
::n.n.n.n/mmm         128 bit cidr notation
::n.n.n.n/::m.m.m.m
::x:x
::x:x/mmm
x:x:x:x:x:x:x:x
x:x:x:x:x:x:x:x/mmm
x:x:x:x:x:x:x:x/m:m:m:m:m:m:m:m any RFC1884 notation
loopback, localhost, unspecified, any, default
::x:x/host
0xABCDEF, 0b111111000101011110 within the limits
of perl's number resolution
123456789012  a 'big' bcd number (bigger than perl likes)
and Math::BigInt

A Fully Qualified Domain Name which returns an ipV4 address or an ipV6 address, embodied in that order. This previously undocumented feature may be disabled with:

use NetAddr::IP::Lite ':nofqdn';

If called with no arguments, 'default' is assumed.

If called with and empty string as the argument, 'undef' is returned;

This method is essential for serializing the representation of a subnet.

10.0.0.0        -   10.255.255.255  (10/8 prefix)
172.16.0.0      -   172.31.255.255  (172.16/12 prefix)
192.168.0.0     -   192.168.255.255 (192.168/16 prefix)

      i.e.    ipV4    127.0.0.0 - 127.255.255.255
or            ipV6    === ::1

Version 4.00 of NetAddr::IP and version 1.00 of NetAddr::IP::Lite implements "->nth($index)" and "->num()" exactly as the documentation states. Previous versions behaved slightly differently and not in a consistent manner.

To use the old behavior for "->nth($index)" and "->num()":

use NetAddr::IP::Lite qw(:old_nth);
old behavior:
NetAddr::IP->new('10/32')->nth(0) == undef
NetAddr::IP->new('10/32')->nth(1) == undef
NetAddr::IP->new('10/31')->nth(0) == undef
NetAddr::IP->new('10/31')->nth(1) == 10.0.0.1/31
NetAddr::IP->new('10/30')->nth(0) == undef
NetAddr::IP->new('10/30')->nth(1) == 10.0.0.1/30
NetAddr::IP->new('10/30')->nth(2) == 10.0.0.2/30
NetAddr::IP->new('10/30')->nth(3) == 10.0.0.3/30

Note that in each case, the broadcast address is represented in the output set and that the 'zero'th index is alway undef except for a point-to-point /31 or /127 network where there are exactly two addresses in the network.

new behavior:
NetAddr::IP->new('10/32')->nth(0)  == 10.0.0.0/32
NetAddr::IP->new('10.1/32'->nth(0) == 10.0.0.1/32
NetAddr::IP->new('10/31')->nth(0)  == 10.0.0.0/32
NetAddr::IP->new('10/31')->nth(1)  == 10.0.0.1/32
NetAddr::IP->new('10/30')->nth(0) == 10.0.0.1/30
NetAddr::IP->new('10/30')->nth(1) == 10.0.0.2/30
NetAddr::IP->new('10/30')->nth(2) == undef

Note that a /32 net always has 1 usable address while a /31 has exactly two usable addresses for point-to-point addressing. The first index (0) returns the address immediately following the network address except for a /31 or /127 when it return the network address.

Version 4.00 of NetAddr::IP and version 1.00 of NetAddr::IP::Lite return the number of usable IP addresses within the subnet, not counting the broadcast or network address.

Previous versions worked only for ipV4 addresses, returned a maximum span of 2**32 and returned the number of IP addresses not counting the broadcast address. (one greater than the new behavior)

To use the old behavior for "->nth($index)" and "->num()":

use NetAddr::IP::Lite qw(:old_nth);

WARNING:

NetAddr::IP will calculate and return a numeric string for network ranges as large as 2**128. These values are TEXT strings and perl can treat them as integers for numeric calculations.

Perl on 32 bit platforms only handles integer numbers up to 2**32 and on 64 bit platforms to 2**64.

If you wish to manipulate numeric strings returned by NetAddr::IP that are larger than 2**32 or 2**64, respectively, you must load additional modules such as Math::BigInt, bignum or some similar package to do the integer math.