is_loopback

Checks whether an IP address is a loopback address.

is_loopback(x:ip) -> bool

Description

The is_loopback function checks whether a given IP address x is a loopback address.

For IPv4, loopback addresses are in the range 127.0.0.0 to 127.255.255.255 (127.0.0.0/8).

For IPv6, the loopback address is ::1.

from {
  ipv4_loopback: 127.0.0.1.is_loopback(),
  ipv6_loopback: ::1.is_loopback(),
  not_loopback: 8.8.8.8.is_loopback(),
}

{
  ipv4_loopback: true,
  ipv6_loopback: true,
  not_loopback: false,
}