/**
 * Extract nested property from object. If nested property cannot be reached, return value of rescue
 * @param obj Object
 * @param path Can be dot-separated  string or array
 * @param rescue (optional) default value. Defaults to null
 */
function extract(obj, path, rescue){

    if (typeof obj === "object" && path){

        var elements = typeof path === "string" ? path.split(".") : path;

        if (typeof elements.shift === "function"){

             var head = elements.shift();

             if (obj.hasOwnProperty(head)){

                return (elements.length === 0) ? obj[head] : extract(obj[head], elements, rescue);

             } // if

         } // if

    } // if

    return rescue || null;

} // extract


var noob = {k1 : {k11 : {k111 : "v1"}}, k2 : { k21 : "v2"}};

console.log(extract(noob, 'k1.k11')); // {k111 : "v1"}
console.log(extract(noob, 'k1.k11.k111')); // v1
console.log(extract(noob, ['k1', 'k11', 'k111'])); // v1
console.log(extract(noob, 'k1.k11.kx')); // null
console.log(extract(noob, 'k2')); //  k2 : { k21 : "v2"}
console.log(extract(noob, 'k2.k21.k22')); // null
console.log(extract(noob, 'k1.k11.k22', "ZUT")); // ZUT
console.log(extract(noob, '', "ZUT"));  // ZUT
console.log(extract(false, '', "ZUT"));  // ZUT

var x = {
  blah: {
     blam: "bloo"
  }
}
with(x) {
  console.log(blah)
}
with(x){
  console.log(blah.blam)
}

var extract = function(obj, path, rescue){
  with(obj) {
    return eval(path) || rescue;
  }
}