irc bot on intersystems cache

#include %occInclude
    kill
    set host="chat.freenode.net"
    set port="6667"
    set sock=##class(%IO.Socket).%New()
    set linepat=##class(%Regex.Matcher).%New("^\:([^\!\ ]+)\![^\ ]+\ (.+)$")
    set privmsg=##class(%Regex.Matcher).%New("^PRIVMSG #([^\ ]+) \:(.+)")
    set action=##class(%Regex.Matcher).%New("!(?:bot|BOT) (.+)")
    
    try {
        if sock.Open(host, port, 100, .tSC) {
            do sock.WriteLine("USER cosbot 0 * :Cache Bot")
            do sock.WriteLine("NICK cosbot")
            do sock.WriteLine("JOIN ##cos")
            do {
                set line=sock.ReadLine(, .5, .tSC)
                if $$$ISERR(tSC) {
                    do $system.OBJ.DisplayError(tSC)
                    quit
                }
                set line=$zstrip(line,"<>C")
                if line'="" {
                    write $c(13),line,!
                }
                if $match(line, "^PING \:([a-zA-Z\-\.0-9]+)$") {
                    set response="PONG "_$extract(line, 7, *)
                    write $c(13),"RESPONSE: "_response,!
                    do sock.WriteLine(response)
                } elseif linepat.Match(line) {
                    set nick=linepat.Group(1)
                    set line=linepat.Group(2)
                    if privmsg.Match(line) {
                        set channel=privmsg.Group(1)
                        set msg=privmsg.Group(2)
                        if action.Match(msg) {
                            set text=action.Group(1)
                            set response="PRIVMSG #"_channel_" :"_nick_", "_text
                            write $c(13),"RESPONSE: "_response,!
                            do sock.WriteLine(response)
                        }
                        continue
                    }
                } else {
                }
                read test:0
                if test'="" {
                    read msg
                    set msg=test_msg
                    quit:msg="q"
                    set response="PRIVMSG ##cos :"_msg
                    write $c(13),"RESPONSE: "_response,!
                    do sock.WriteLine(response)
                }
            } while 1
        } else {
            do $system.OBJ.DisplayError(tSC)
        }
        do sock.WriteLine("QUIT :bye-bye")
    } catch {}
    write !,sock.Close()
    quit