Networking Primitives

Joa treats IPv4 addresses and CIDR subnets as distinct native types, not strings. This prevents accidental misuse and enables type-safe network operations.

IP Literals

Any dotted-quad address is automatically parsed as an IP type:

let gateway    = 192.168.1.1
let dns_server = 8.8.8.8
let loopback   = 127.0.0.1

An invalid address causes a Type Error at runtime.

Subnet Literals

Any CIDR notation is automatically parsed as a Subnet type:

let lan       = 192.168.0.0/16
let dmz       = 10.10.10.0/24
let host_only = 172.16.0.1/32

IP Membership

The in / not in operators work natively between IP and Subnet:

let zone = 10.0.0.0/8
let host = 10.5.3.2

if host in zone {
    print("Host is inside the zone")
}

if 172.16.0.1 not in zone {
    print("External address detected")
}

Subnet Properties

let net = 192.168.1.0/24
print(net.network)   // 192.168.1.0
print(net.mask)      // 24

Subnet Methods

See §16 Subnet Methods.