gistfile1.txt

var xhr = (function() {
    var XHR = function() {
        var xmlhttp = false;
        try {
            xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            try {
                xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (E) {
                xmlhttp = false;
            }
        }
        if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
            try {
                xmlhttp = new XMLHttpRequest();
            } catch (e) {
                xmlhttp = false;
            }
        }
        this.xmlhttp = xmlhttp;
    };
    XHR.prototype.post = function(options) {
        this.request.apply(this, ["POST", options]);
    };
    XHR.prototype.get = function(options) {
        this.request.apply(this, ["GET", options]);
    };
    XHR.prototype.request = function(type, options) {
        if (this.xmlhttp) {
            var _xhr = this.xmlhttp;
            _xhr.open(type, options.url, true);
            _xhr.onreadystatechange = function() {
                if (_xhr.readyState == 4) {
                    options.success.apply(this, [_xhr.responseText]);
                }
                // add failure callback
            };
            _xhr.send(null);
        }
    };
    return new XHR();
})();