gistfile1.js

var supportDefineProperty = (function () {
    var i = 0;
    var getter = function () {
        if (i === 0) {
            throw new Error("Execute too soon.");
        }
        
        return i;
    };

    var obj = {};
    
    try {
        Object.defineProperty(obj, "value", { get: getter });

        i = 1;
        return obj.value === 1;
    } catch (ex) {
        return false;
    }
})();