node-analytics.js
function getSystem(cb){
        var agent = useragent.parse(req.headers['user-agent']);
        var os = agent.os;

        if(!session.system)
            session.system = {};

        if(!session.system.browser)
            session.system.browser = {};
        if(!session.system.os)
            session.system.os = {};

        session.system.browser.name = agent.family;
        session.system.browser.version = agent.major + '.' + agent.minor + '.' + agent.patch;

        session.system.os.name = os.family;
        session.system.os.version = os.major + '.' + os.minor + '.' + os.patch;

        cb(null)
    }
function getSystem(cb){
        var agent = useragent.parse(req.headers['user-agent']);
        var os = agent.os;

        if(!session.system)
            session.system = {};

        if(!session.system.browser)
            session.system.browser = {};
        if(!session.system.os)
            session.system.os = {};

        session.system.browser.name = agent.family;
        session.system.browser.version = agent.major + '.' + agent.minor + '.' + agent.patch;

        session.system.os.name = os.family;
        session.system.os.version = os.major + '.' + os.minor + '.' + os.patch;

        cb(null)
    }
function getSystem ( cb ) { var agent = useragent . parse ( req . headers [ 'user-agent' ] ) ; var os = agent . os ; if ( ! session . system ) session . system = { } ; if ( ! session . system . browser ) session . system . browser = { } ; if ( ! session . system . os ) session . system . os = { } ; session . system . browser . name = agent . family ; session . system . browser . version = agent . major + '.' + agent . minor + '.' + agent . patch ; session . system . os . name = os . family ; session . system . os . version = os . major + '.' + os . minor + '.' + os . patch ; cb ( null ) }
.system :: .os{, .broswer{ .name, .version
. system :: . os { . broswer { . name . version