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function getParent(snapshot) {
  // You can get the reference (A Firebase object) from a snapshot
  // using .ref().
  var ref = snapshot.ref();
  // Now simply find the parent and return the name.
  return ref.parent().name();
}
 
var testRef = new Firebase("https://example.firebaseIO-demo.com/foo/bar");
testRef.once("value", function(snapshot) {

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function pushSomething(ref) {
  // Let's push something. push() returns a reference that you can hold onto!
  var justPushed = ref.push({test: "push"});
  // We return a reference, but you can also return the name of the newly
  // created object with .name().
  return justPushed;
}
 
function removeItem(ref) {
  // Now we can get back to that item we just pushed via .child().

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function go() {
  var userId = prompt('Username?', 'Guest');
  // Consider adding '/<unique id>' if you have multiple games.
  var gameRef = new Firebase(GAME_LOCATION);
  assignPlayerNumberAndPlayGame(userId, gameRef);
};
 
// The maximum number of players.  If there are already 
// NUM_PLAYERS assigned, users won't be able to join the game.
var NUM_PLAYERS = 4;

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function go() {
  var userId = prompt('Username?', 'Guest');
  var userData = { name: userId };
  tryCreateUser(userId, userData);
}
 
var USERS_LOCATION = 'https://SampleChat.firebaseIO-demo.com/users';
 
function userCreated(userId, success) {
  if (!success) {

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// Helper function to extract claims from a JWT. Does *not* verify the
// validity of the token. 
// credits: https://github.com/firebase/angularFire/blob/master/angularFire.js#L370
// polyfill window.atob() for IE8: https://github.com/davidchambers/Base64.js
// or really fast Base64 by Fred Palmer: https://code.google.com/p/javascriptbase64/
function deconstructJWT(token) {
   var segments = token.split(".");
   if (!segments instanceof Array || segments.length !== 3) {
      throw new Error("Invalid JWT");
   }

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// pros: does not fetch entire record set
// cons: grabs the last record which needs to be ignored
var first = true;
var ref = new Firebase(...);
ref.endAt().limit(1).on("child_added", function(snap) {
   if( first ) {
       first = false; 
   } 
   else {
       console.log('new record', snap.val());

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function makeList(ref) {
  var fruits = ["banana", "apple", "grape", "orange"];
  for (var i = 0; i < fruits.length; i++) {
    ref.push(fruits[i]);
  }
}
 
function getFirstFromList(ref, cb) {
  ref.startAt().limit(1).once("child_added", function(snapshot) {
    cb(snapshot.val());

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/* 

This example shows how you can use your data structure as a basis for 
your Firebase security rules to implement role-based security. We store
each user by their Twitter uid, and use the following simplistic approach
for user roles:

0 - GUEST
10 - USER
20 - MODERATOR

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/***************************************************
 * Assuming you can't use priorities (e.g. they are already being used for something else)
 * You can store the email addresses in an index and use that to match them to user ids
 ***************************************************/
 
var fb = new Firebase(URL);
 
/**
 * Looks up a user id by email address and invokes callback with the id or null if not found
 * @return {Object|null} the object contains the key/value hash for one user

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function go() {
  var userId = prompt('Username?', 'Guest');
  checkIfUserExists(userId);
}
 
var USERS_LOCATION = 'https://SampleChat.wilddogio.com/users';
 
function userExistsCallback(userId, exists) {
  if (exists) {
    alert('user ' + userId + ' exists!');