Rhino "_private" naming convention.js

/* by Dmitry A. Soshnikov */

var object = (function () {

    // private
    var _x = 10;

    // also private
    function _privateFunc() {
        return _x;
    }

    // public
    function publicFunc() {
        return 10 + _privateFunc();
    }

    // exports return only public properties/methods
    return exports(/*AO*/function () {}.__parent__);

})();

function exports(AO) {

    var
        hasOwn = Object.prototype.hasOwnProperty,
        api = {};

    for (var property in AO) if (hasOwn.call(AO, property)) {
        if (property.charAt(0) == '_') {
            continue;
        }
        api[property] = AO[property];
    }

    return api;
}

print("publicFunc" in object); // true
print("_privateFunc" in object); // false

// arguments also has been exported
// but can be filtered
print("arguments" in object); // true

print(object.publicFunc()); // 20
print(object._privateFunc()); // Error