library test

var Lib = (function(){
    
    function _private(){
        console.log('private function!');
    }
    var lib = {
        test: function(){
            _private();
            return this;
        },
        other: function(){
            console.log('other test!');
            return this;
        }
    }
    return lib;
})();

Lib
    .test()
    .other();