rust/src/lib/net.rs

import str;
import vec;
import uint;

tag ip_addr {
    ipv4(u8, u8, u8, u8);
}

fn format_addr(ip : ip_addr) -> str {
    alt(ip) {
      ipv4(a, b, c, d) {
        #fmt("%u.%u.%u.%u",
             a as uint,
             b as uint,
             c as uint,
             d as uint)
      }
      _ { fail "Unsupported address type"; }
    }
}

fn parse_addr(ip : str) -> ip_addr {
    let parts = vec::map(uint::from_str, str::split(ip, ".".(0)));
    if vec::len(parts) != 4u { fail "Too many dots in IP address"; }
    for i in parts { if i > 255u { fail "Invalid IP Address part."; } }
    ipv4(parts.(0) as u8,
         parts.(1) as u8,
         parts.(2) as u8,
         parts.(3) as u8)
}