Get IP addresses on local machine (using only F# stdlib)

ips.fsx

open System
open System.Net
open System.Linq

let applyFilters showIPv4Only showIPv6Only addrs =
    match (showIPv4Only, showIPv6Only) with
    | (true, false) -> Seq.filter (fun (addr: IPAddress) -> addr.AddressFamily = Sockets.AddressFamily.InterNetwork) addrs
    | (false, true) -> Seq.filter (fun (addr: IPAddress) -> addr.AddressFamily = Sockets.AddressFamily.InterNetworkV6) addrs
    | (_, _) -> addrs

type CLIArgs = {
    ipv4Only: bool;
    ipv6Only: bool;
}

let parse_args args : CLIArgs = 
    let ipv4Only = Array.contains "-4" args in
    let ipv6Only = Array.contains "-6" args in
    {ipv4Only = ipv4Only; ipv6Only = ipv6Only}
    
let () =
    let args = parse_args (System.Environment.GetCommandLineArgs()) in
    NetworkInformation.NetworkInterface.GetAllNetworkInterfaces()
        |> Array.toSeq
        |> Seq.filter (fun iface -> iface.NetworkInterfaceType <> NetworkInformation.NetworkInterfaceType.Loopback)
        |> Seq.map (fun x -> x.GetIPProperties())
        |> Seq.collect (fun x -> x.UnicastAddresses)
        |> Seq.map (fun addrObj -> addrObj.Address)
        |> (applyFilters args.ipv4Only args.ipv6Only)
        |> Seq.iter (printfn "%A")