ember.js

// Version: v1.0.0-pre.2-396-g99357c2
// Last commit: 99357c2 (2013-01-14 11:38:40 +0000)


(function() {
/*global __fail__*/

/**
Ember Debug

@module ember
@submodule ember-debug
*/

/**
@class Ember
*/

if ('undefined' === typeof Ember) {
  Ember = {};

  if ('undefined' !== typeof window) {
    window.Em = window.Ember = Em = Ember;
  }
}

Ember.ENV = 'undefined' === typeof ENV ? {} : ENV;

if (!('MANDATORY_SETTER' in Ember.ENV)) {
  Ember.ENV.MANDATORY_SETTER = true; // default to true for debug dist
}

/**
  Define an assertion that will throw an exception if the condition is not
  met. Ember build tools will remove any calls to `Ember.assert()` when
  doing a production build. Example:

  ```javascript
  // Test for truthiness
  Ember.assert('Must pass a valid object', obj);
  // Fail unconditionally
  Ember.assert('This code path should never be run')
  ```

  @method assert
  @param {String} desc A description of the assertion. This will become
    the text of the Error thrown if the assertion fails.
  @param {Boolean} test Must be truthy for the assertion to pass. If
    falsy, an exception will be thrown.
*/
Ember.assert = function(desc, test) {
  if (!test) throw new Error("assertion failed: "+desc);
};


/**
  Display a warning with the provided message. Ember build tools will
  remove any calls to `Ember.warn()` when doing a production build.

  @method warn
  @param {String} message A warning to display.
  @param {Boolean} test An optional boolean. If falsy, the warning
    will be displayed.
*/
Ember.warn = function(message, test) {
  if (!test) {
    Ember.Logger.warn("WARNING: "+message);
    if ('trace' in Ember.Logger) Ember.Logger.trace();
  }
};

/**
  Display a deprecation warning with the provided message and a stack trace
  (Chrome and Firefox only). Ember build tools will remove any calls to
  `Ember.deprecate()` when doing a production build.

  @method deprecate
  @param {String} message A description of the deprecation.
  @param {Boolean} test An optional boolean. If falsy, the deprecation
    will be displayed.
*/
Ember.deprecate = function(message, test) {
  if (Ember && Ember.TESTING_DEPRECATION) { return; }

  if (arguments.length === 1) { test = false; }
  if (test) { return; }

  if (Ember && Ember.ENV.RAISE_ON_DEPRECATION) { throw new Error(message); }

  var error;

  // When using new Error, we can't do the arguments check for Chrome. Alternatives are welcome
  try { __fail__.fail(); } catch (e) { error = e; }

  if (Ember.LOG_STACKTRACE_ON_DEPRECATION && error.stack) {
    var stack, stackStr = '';
    if (error['arguments']) {
      // Chrome
      stack = error.stack.replace(/^\s+at\s+/gm, '').
                          replace(/^([^\(]+?)([\n$])/gm, '{anonymous}($1)$2').
                          replace(/^Object.<anonymous>\s*\(([^\)]+)\)/gm, '{anonymous}($1)').split('\n');
      stack.shift();
    } else {
      // Firefox
      stack = error.stack.replace(/(?:\n@:0)?\s+$/m, '').
                          replace(/^\(/gm, '{anonymous}(').split('\n');
    }

    stackStr = "\n    " + stack.slice(2).join("\n    ");
    message = message + stackStr;
  }

  Ember.Logger.warn("DEPRECATION: "+message);
};



/**
  Display a deprecation warning with the provided message and a stack trace
  (Chrome and Firefox only) when the wrapped method is called.

  Ember build tools will not remove calls to `Ember.deprecateFunc()`, though
  no warnings will be shown in production.

  @method deprecateFunc
  @param {String} message A description of the deprecation.
  @param {Function} func The function to be deprecated.
*/
Ember.deprecateFunc = function(message, func) {
  return function() {
    Ember.deprecate(message);
    return func.apply(this, arguments);
  };
};

if ('undefined' !== typeof window) {
  window.ember_assert         = Ember.deprecateFunc("ember_assert is deprecated. Please use Ember.assert instead.",               Ember.assert);
  window.ember_warn           = Ember.deprecateFunc("ember_warn is deprecated. Please use Ember.warn instead.",                   Ember.warn);
  window.ember_deprecate      = Ember.deprecateFunc("ember_deprecate is deprecated. Please use Ember.deprecate instead.",         Ember.deprecate);
  window.ember_deprecateFunc  = Ember.deprecateFunc("ember_deprecateFunc is deprecated. Please use Ember.deprecateFunc instead.", Ember.deprecateFunc);
}

})();

// Version: v1.0.0-pre.2-408-g43354a9
// Last commit: 43354a9 (2013-01-15 18:12:34 -0800)


(function() {
var define, requireModule;

(function() {
  var registry = {}, seen = {};

  define = function(name, deps, callback) {
    registry[name] = { deps: deps, callback: callback };
  };

  requireModule = function(name) {
    if (seen[name]) { return seen[name]; }
    seen[name] = {};

    var mod = registry[name],
        deps = mod.deps,
        callback = mod.callback,
        reified = [],
        exports;

    for (var i=0, l=deps.length; i<l; i++) {
      if (deps[i] === 'exports') {
        reified.push(exports = {});
      } else {
        reified.push(requireModule(deps[i]));
      }
    }

    var value = callback.apply(this, reified);
    return seen[name] = exports || value;
  };
})();
(function() {
/*globals Em:true ENV */

/**
@module ember
@submodule ember-metal
*/

/**
  All Ember methods and functions are defined inside of this namespace. You
  generally should not add new properties to this namespace as it may be
  overwritten by future versions of Ember.

  You can also use the shorthand `Em` instead of `Ember`.

  Ember-Runtime is a framework that provides core functions for Ember including
  cross-platform functions, support for property observing and objects. Its
  focus is on small size and performance. You can use this in place of or
  along-side other cross-platform libraries such as jQuery.

  The core Runtime framework is based on the jQuery API with a number of
  performance optimizations.

  @class Ember
  @static
  @version 1.0.0-pre.2
*/

if ('undefined' === typeof Ember) {
  // Create core object. Make it act like an instance of Ember.Namespace so that
  // objects assigned to it are given a sane string representation.
  Ember = {};
}

// Default imports, exports and lookup to the global object;
var imports = Ember.imports = Ember.imports || this;
var exports = Ember.exports = Ember.exports || this;
var lookup  = Ember.lookup  = Ember.lookup  || this;

// aliases needed to keep minifiers from removing the global context
exports.Em = exports.Ember = Em = Ember;

// Make sure these are set whether Ember was already defined or not

Ember.isNamespace = true;

Ember.toString = function() { return "Ember"; };


/**
  @property VERSION
  @type String
  @default '1.0.0-pre.2'
  @final
*/
Ember.VERSION = '1.0.0-pre.2';

/**
  Standard environmental variables. You can define these in a global `ENV`
  variable before loading Ember to control various configuration
  settings.

  @property ENV
  @type Hash
*/
Ember.ENV = Ember.ENV || ('undefined' === typeof ENV ? {} : ENV);

Ember.config = Ember.config || {};

// ..........................................................
// BOOTSTRAP
//

/**
  Determines whether Ember should enhances some built-in object prototypes to
  provide a more friendly API. If enabled, a few methods will be added to
  `Function`, `String`, and `Array`. `Object.prototype` will not be enhanced,
  which is the one that causes most trouble for people.

  In general we recommend leaving this option set to true since it rarely
  conflicts with other code. If you need to turn it off however, you can
  define an `ENV.EXTEND_PROTOTYPES` config to disable it.

  @property EXTEND_PROTOTYPES
  @type Boolean
  @default true
*/
Ember.EXTEND_PROTOTYPES = Ember.ENV.EXTEND_PROTOTYPES;

if (typeof Ember.EXTEND_PROTOTYPES === 'undefined') {
  Ember.EXTEND_PROTOTYPES = true;
}

/**
  Determines whether Ember logs a full stack trace during deprecation warnings

  @property LOG_STACKTRACE_ON_DEPRECATION
  @type Boolean
  @default true
*/
Ember.LOG_STACKTRACE_ON_DEPRECATION = (Ember.ENV.LOG_STACKTRACE_ON_DEPRECATION !== false);

/**
  Determines whether Ember should add ECMAScript 5 shims to older browsers.

  @property SHIM_ES5
  @type Boolean
  @default Ember.EXTEND_PROTOTYPES
*/
Ember.SHIM_ES5 = (Ember.ENV.SHIM_ES5 === false) ? false : Ember.EXTEND_PROTOTYPES;

/**
  Empty function. Useful for some operations.

  @method K
  @private
  @return {Object}
*/
Ember.K = function() { return this; };


// Stub out the methods defined by the ember-debug package in case it's not loaded

if ('undefined' === typeof Ember.assert) { Ember.assert = Ember.K; }
if ('undefined' === typeof Ember.warn) { Ember.warn = Ember.K; }
if ('undefined' === typeof Ember.deprecate) { Ember.deprecate = Ember.K; }
if ('undefined' === typeof Ember.deprecateFunc) {
  Ember.deprecateFunc = function(_, func) { return func; };
}

// These are deprecated but still supported

if ('undefined' === typeof ember_assert) { exports.ember_assert = Ember.K; }
if ('undefined' === typeof ember_warn) { exports.ember_warn = Ember.K; }
if ('undefined' === typeof ember_deprecate) { exports.ember_deprecate = Ember.K; }
if ('undefined' === typeof ember_deprecateFunc) {
  exports.ember_deprecateFunc = function(_, func) { return func; };
}

/**
  Previously we used `Ember.$.uuid`, however `$.uuid` has been removed from
  jQuery master. We'll just bootstrap our own uuid now.

  @property uuid
  @type Number
  @private
*/
Ember.uuid = 0;

// ..........................................................
// LOGGER
//

/**
  Inside Ember-Metal, simply uses the `imports.console` object.
  Override this to provide more robust logging functionality.

  @class Logger
  @namespace Ember
*/
Ember.Logger = imports.console || { log: Ember.K, warn: Ember.K, error: Ember.K, info: Ember.K, debug: Ember.K };


// ..........................................................
// ERROR HANDLING
//

/**
  A function may be assigned to `Ember.onerror` to be called when Ember
  internals encounter an error. This is useful for specialized error handling
  and reporting code.

  @event onerror
  @for Ember
  @param {Exception} error the error object
*/
Ember.onerror = null;

/**
  @private

  Wrap code block in a try/catch if {{#crossLink "Ember/onerror"}}{{/crossLink}} is set.

  @method handleErrors
  @for Ember
  @param {Function} func
  @param [context]
*/
Ember.handleErrors = function(func, context) {
  // Unfortunately in some browsers we lose the backtrace if we rethrow the existing error,
  // so in the event that we don't have an `onerror` handler we don't wrap in a try/catch
  if ('function' === typeof Ember.onerror) {
    try {
      return func.apply(context || this);
    } catch (error) {
      Ember.onerror(error);
    }
  } else {
    return func.apply(context || this);
  }
};

Ember.merge = function(original, updates) {
  for (var prop in updates) {
    if (!updates.hasOwnProperty(prop)) { continue; }
    original[prop] = updates[prop];
  }
};

})();



(function() {
/*globals Node */
/**
@module ember-metal
*/

/**
  Platform specific methods and feature detectors needed by the framework.

  @class platform
  @namespace Ember
  @static
*/
var platform = Ember.platform = {};


/**
  Identical to `Object.create()`. Implements if not available natively.

  @method create
  @for Ember
*/
Ember.create = Object.create;

// STUB_OBJECT_CREATE allows us to override other libraries that stub
// Object.create different than we would prefer
if (!Ember.create || Ember.ENV.STUB_OBJECT_CREATE) {
  var K = function() {};

  Ember.create = function(obj, props) {
    K.prototype = obj;
    obj = new K();
    if (props) {
      K.prototype = obj;
      for (var prop in props) {
        K.prototype[prop] = props[prop].value;
      }
      obj = new K();
    }
    K.prototype = null;

    return obj;
  };

  Ember.create.isSimulated = true;
}

var defineProperty = Object.defineProperty;
var canRedefineProperties, canDefinePropertyOnDOM;

// Catch IE8 where Object.defineProperty exists but only works on DOM elements
if (defineProperty) {
  try {
    defineProperty({}, 'a',{get:function(){}});
  } catch (e) {
    defineProperty = null;
  }
}

if (defineProperty) {
  // Detects a bug in Android <3.2 where you cannot redefine a property using
  // Object.defineProperty once accessors have already been set.
  canRedefineProperties = (function() {
    var obj = {};

    defineProperty(obj, 'a', {
      configurable: true,
      enumerable: true,
      get: function() { },
      set: function() { }
    });

    defineProperty(obj, 'a', {
      configurable: true,
      enumerable: true,
      writable: true,
      value: true
    });

    return obj.a === true;
  })();

  // This is for Safari 5.0, which supports Object.defineProperty, but not
  // on DOM nodes.
  canDefinePropertyOnDOM = (function(){
    try {
      defineProperty(document.createElement('div'), 'definePropertyOnDOM', {});
      return true;
    } catch(e) { }

    return false;
  })();

  if (!canRedefineProperties) {
    defineProperty = null;
  } else if (!canDefinePropertyOnDOM) {
    defineProperty = function(obj, keyName, desc){
      var isNode;

      if (typeof Node === "object") {
        isNode = obj instanceof Node;
      } else {
        isNode = typeof obj === "object" && typeof obj.nodeType === "number" && typeof obj.nodeName === "string";
      }

      if (isNode) {
        // TODO: Should we have a warning here?
        return (obj[keyName] = desc.value);
      } else {
        return Object.defineProperty(obj, keyName, desc);
      }
    };
  }
}

/**
@class platform
@namespace Ember
*/

/**
  Identical to `Object.defineProperty()`. Implements as much functionality
  as possible if not available natively.

  @method defineProperty
  @param {Object} obj The object to modify
  @param {String} keyName property name to modify
  @param {Object} desc descriptor hash
  @return {void}
*/
platform.defineProperty = defineProperty;

/**
  Set to true if the platform supports native getters and setters.

  @property hasPropertyAccessors
  @final
*/
platform.hasPropertyAccessors = true;

if (!platform.defineProperty) {
  platform.hasPropertyAccessors = false;

  platform.defineProperty = function(obj, keyName, desc) {
    if (!desc.get) { obj[keyName] = desc.value; }
  };

  platform.defineProperty.isSimulated = true;
}

if (Ember.ENV.MANDATORY_SETTER && !platform.hasPropertyAccessors) {
  Ember.ENV.MANDATORY_SETTER = false;
}

})();



(function() {
/**
@module ember-metal
*/


var o_defineProperty = Ember.platform.defineProperty,
    o_create = Ember.create,
    // Used for guid generation...
    GUID_KEY = '__ember'+ (+ new Date()),
    uuid         = 0,
    numberCache  = [],
    stringCache  = {};

var MANDATORY_SETTER = Ember.ENV.MANDATORY_SETTER;

/**
  @private

  A unique key used to assign guids and other private metadata to objects.
  If you inspect an object in your browser debugger you will often see these.
  They can be safely ignored.

  On browsers that support it, these properties are added with enumeration
  disabled so they won't show up when you iterate over your properties.

  @property GUID_KEY
  @for Ember
  @type String
  @final
*/
Ember.GUID_KEY = GUID_KEY;

var GUID_DESC = {
  writable:    false,
  configurable: false,
  enumerable:  false,
  value: null
};

/**
  @private

  Generates a new guid, optionally saving the guid to the object that you
  pass in. You will rarely need to use this method. Instead you should
  call `Ember.guidFor(obj)`, which return an existing guid if available.

  @method generateGuid
  @for Ember
  @param {Object} [obj] Object the guid will be used for. If passed in, the guid will
    be saved on the object and reused whenever you pass the same object
    again.

    If no object is passed, just generate a new guid.
  @param {String} [prefix] Prefix to place in front of the guid. Useful when you want to
    separate the guid into separate namespaces.
  @return {String} the guid
*/
Ember.generateGuid = function generateGuid(obj, prefix) {
  if (!prefix) prefix = 'ember';
  var ret = (prefix + (uuid++));
  if (obj) {
    GUID_DESC.value = ret;
    o_defineProperty(obj, GUID_KEY, GUID_DESC);
  }
  return ret ;
};

/**
  @private

  Returns a unique id for the object. If the object does not yet have a guid,
  one will be assigned to it. You can call this on any object,
  `Ember.Object`-based or not, but be aware that it will add a `_guid`
  property.

  You can also use this method on DOM Element objects.

  @method guidFor
  @for Ember
  @param obj {Object} any object, string, number, Element, or primitive
  @return {String} the unique guid for this instance.
*/
Ember.guidFor = function guidFor(obj) {

  // special cases where we don't want to add a key to object
  if (obj === undefined) return "(undefined)";
  if (obj === null) return "(null)";

  var cache, ret;
  var type = typeof obj;

  // Don't allow prototype changes to String etc. to change the guidFor
  switch(type) {
    case 'number':
      ret = numberCache[obj];
      if (!ret) ret = numberCache[obj] = 'nu'+obj;
      return ret;

    case 'string':
      ret = stringCache[obj];
      if (!ret) ret = stringCache[obj] = 'st'+(uuid++);
      return ret;

    case 'boolean':
      return obj ? '(true)' : '(false)';

    default:
      if (obj[GUID_KEY]) return obj[GUID_KEY];
      if (obj === Object) return '(Object)';
      if (obj === Array)  return '(Array)';
      ret = 'ember'+(uuid++);
      GUID_DESC.value = ret;
      o_defineProperty(obj, GUID_KEY, GUID_DESC);
      return ret;
  }
};

// ..........................................................
// META
//

var META_DESC = {
  writable:    true,
  configurable: false,
  enumerable:  false,
  value: null
};

var META_KEY = Ember.GUID_KEY+'_meta';

/**
  The key used to store meta information on object for property observing.

  @property META_KEY
  @for Ember
  @private
  @final
  @type String
*/
Ember.META_KEY = META_KEY;

// Placeholder for non-writable metas.
var EMPTY_META = {
  descs: {},
  watching: {}
};

if (MANDATORY_SETTER) { EMPTY_META.values = {}; }

Ember.EMPTY_META = EMPTY_META;

if (Object.freeze) Object.freeze(EMPTY_META);

var isDefinePropertySimulated = Ember.platform.defineProperty.isSimulated;

function Meta(obj) {
  this.descs = {};
  this.watching = {};
  this.cache = {};
  this.source = obj;
}

if (isDefinePropertySimulated) {
  // on platforms that don't support enumerable false
  // make meta fail jQuery.isPlainObject() to hide from
  // jQuery.extend() by having a property that fails
  // hasOwnProperty check.
  Meta.prototype.__preventPlainObject__ = true;

  // Without non-enumerable properties, meta objects will be output in JSON
  // unless explicitly suppressed
  Meta.prototype.toJSON = function () { };
}

/**
  Retrieves the meta hash for an object. If `writable` is true ensures the
  hash is writable for this object as well.

  The meta object contains information about computed property descriptors as
  well as any watched properties and other information. You generally will
  not access this information directly but instead work with higher level
  methods that manipulate this hash indirectly.

  @method meta
  @for Ember
  @private

  @param {Object} obj The object to retrieve meta for
  @param {Boolean} [writable=true] Pass `false` if you do not intend to modify
    the meta hash, allowing the method to avoid making an unnecessary copy.
  @return {Hash}
*/
Ember.meta = function meta(obj, writable) {

  var ret = obj[META_KEY];
  if (writable===false) return ret || EMPTY_META;

  if (!ret) {
    if (!isDefinePropertySimulated) o_defineProperty(obj, META_KEY, META_DESC);

    ret = new Meta(obj);

    if (MANDATORY_SETTER) { ret.values = {}; }

    obj[META_KEY] = ret;

    // make sure we don't accidentally try to create constructor like desc
    ret.descs.constructor = null;

  } else if (ret.source !== obj) {
    if (!isDefinePropertySimulated) o_defineProperty(obj, META_KEY, META_DESC);

    ret = o_create(ret);
    ret.descs    = o_create(ret.descs);
    ret.watching = o_create(ret.watching);
    ret.cache    = {};
    ret.source   = obj;

    if (MANDATORY_SETTER) { ret.values = o_create(ret.values); }

    obj[META_KEY] = ret;
  }
  return ret;
};

Ember.getMeta = function getMeta(obj, property) {
  var meta = Ember.meta(obj, false);
  return meta[property];
};

Ember.setMeta = function setMeta(obj, property, value) {
  var meta = Ember.meta(obj, true);
  meta[property] = value;
  return value;
};

/**
  @private

  In order to store defaults for a class, a prototype may need to create
  a default meta object, which will be inherited by any objects instantiated
  from the class's constructor.

  However, the properties of that meta object are only shallow-cloned,
  so if a property is a hash (like the event system's `listeners` hash),
  it will by default be shared across all instances of that class.

  This method allows extensions to deeply clone a series of nested hashes or
  other complex objects. For instance, the event system might pass
  `['listeners', 'foo:change', 'ember157']` to `prepareMetaPath`, which will
  walk down the keys provided.

  For each key, if the key does not exist, it is created. If it already
  exists and it was inherited from its constructor, the constructor's
  key is cloned.

  You can also pass false for `writable`, which will simply return
  undefined if `prepareMetaPath` discovers any part of the path that
  shared or undefined.

  @method metaPath
  @for Ember
  @param {Object} obj The object whose meta we are examining
  @param {Array} path An array of keys to walk down
  @param {Boolean} writable whether or not to create a new meta
    (or meta property) if one does not already exist or if it's
    shared with its constructor
*/
Ember.metaPath = function metaPath(obj, path, writable) {
  var meta = Ember.meta(obj, writable), keyName, value;

  for (var i=0, l=path.length; i<l; i++) {
    keyName = path[i];
    value = meta[keyName];

    if (!value) {
      if (!writable) { return undefined; }
      value = meta[keyName] = { __ember_source__: obj };
    } else if (value.__ember_source__ !== obj) {
      if (!writable) { return undefined; }
      value = meta[keyName] = o_create(value);
      value.__ember_source__ = obj;
    }

    meta = value;
  }

  return value;
};

/**
  @private

  Wraps the passed function so that `this._super` will point to the superFunc
  when the function is invoked. This is the primitive we use to implement
  calls to super.

  @method wrap
  @for Ember
  @param {Function} func The function to call
  @param {Function} superFunc The super function.
  @return {Function} wrapped function.
*/
Ember.wrap = function(func, superFunc) {
  function K() {}

  function superWrapper() {
    var ret, sup = this._super;
    this._super = superFunc || K;
    ret = func.apply(this, arguments);
    this._super = sup;
    return ret;
  }

  superWrapper.wrappedFunction = func;
  superWrapper.__ember_observes__ = func.__ember_observes__;
  superWrapper.__ember_observesBefore__ = func.__ember_observesBefore__;

  return superWrapper;
};

/**
  Returns true if the passed object is an array or Array-like.

  Ember Array Protocol:

    - the object has an objectAt property
    - the object is a native Array
    - the object is an Object, and has a length property

  Unlike `Ember.typeOf` this method returns true even if the passed object is
  not formally array but appears to be array-like (i.e. implements `Ember.Array`)

  ```javascript
  Ember.isArray();                                            // false
  Ember.isArray([]);                                          // true
  Ember.isArray( Ember.ArrayProxy.create({ content: [] }) );  // true
  ```

  @method isArray
  @for Ember
  @param {Object} obj The object to test
  @return {Boolean}
*/
Ember.isArray = function(obj) {
  if (!obj || obj.setInterval) { return false; }
  if (Array.isArray && Array.isArray(obj)) { return true; }
  if (Ember.Array && Ember.Array.detect(obj)) { return true; }
  if ((obj.length !== undefined) && 'object'===typeof obj) { return true; }
  return false;
};

/**
  Forces the passed object to be part of an array. If the object is already
  an array or array-like, returns the object. Otherwise adds the object to
  an array. If obj is `null` or `undefined`, returns an empty array.

  ```javascript
  Ember.makeArray();                           // []
  Ember.makeArray(null);                       // []
  Ember.makeArray(undefined);                  // []
  Ember.makeArray('lindsay');                  // ['lindsay']
  Ember.makeArray([1,2,42]);                   // [1,2,42]

  var controller = Ember.ArrayProxy.create({ content: [] });
  Ember.makeArray(controller) === controller;  // true
  ```

  @method makeArray
  @for Ember
  @param {Object} obj the object
  @return {Array}
*/
Ember.makeArray = function(obj) {
  if (obj === null || obj === undefined) { return []; }
  return Ember.isArray(obj) ? obj : [obj];
};

function canInvoke(obj, methodName) {
  return !!(obj && typeof obj[methodName] === 'function');
}

/**
  Checks to see if the `methodName` exists on the `obj`.

  @method canInvoke
  @for Ember
  @param {Object} obj The object to check for the method
  @param {String} methodName The method name to check for
*/
Ember.canInvoke = canInvoke;

/**
  Checks to see if the `methodName` exists on the `obj`,
  and if it does, invokes it with the arguments passed.

  @method tryInvoke
  @for Ember
  @param {Object} obj The object to check for the method
  @param {String} methodName The method name to check for
  @param {Array} [args] The arguments to pass to the method
  @return {anything} the return value of the invoked method or undefined if it cannot be invoked
*/
Ember.tryInvoke = function(obj, methodName, args) {
  if (canInvoke(obj, methodName)) {
    return obj[methodName].apply(obj, args || []);
  }
};

// https://github.com/emberjs/ember.js/pull/1617
var needsFinallyFix = (function() {
  var count = 0;
  try{
    try { }
    finally {
      count++;
      throw new Error('needsFinallyFixTest');
    }
  } catch (e) {}

  return count !== 1;
})();

/**
  Provides try { } finally { } functionality, while working
  around Safari's double finally bug.

  @method tryFinally
  @for Ember
  @param {Function} function The function to run the try callback
  @param {Function} function The function to run the finally callback
  @param [binding]
  @return {anything} The return value is the that of the finalizer,
  unless that valueis undefined, in which case it is the return value
  of the tryable
*/

if (needsFinallyFix) {
  Ember.tryFinally = function(tryable, finalizer, binding) {
    var result, finalResult, finalError;

    binding = binding || this;

    try {
      result = tryable.call(binding);
    } finally {
      try {
        finalResult = finalizer.call(binding);
      } catch (e){
        finalError = e;
      }
    }

    if (finalError) { throw finalError; }

    return (finalResult === undefined) ? result : finalResult;
  };
} else {
  Ember.tryFinally = function(tryable, finalizer, binding) {
    var result, finalResult;

    binding = binding || this;

    try {
      result = tryable.call(binding);
    } finally {
      finalResult = finalizer.call(binding);
    }

    return (finalResult === undefined) ? result : finalResult;
  };
}

/**
  Provides try { } catch finally { } functionality, while working
  around Safari's double finally bug.

  @method tryCatchFinally
  @for Ember
  @param {Function} function The function to run the try callback
  @param {Function} function The function to run the catchable callback
  @param {Function} function The function to run the finally callback
  @param [binding]
  @return {anything} The return value is the that of the finalizer,
  unless that value is undefined, in which case it is the return value
  of the tryable.
*/
if (needsFinallyFix) {
  Ember.tryCatchFinally = function(tryable, catchable, finalizer, binding) {
    var result, finalResult, finalError, finalReturn;

    binding = binding || this;

    try {
      result = tryable.call(binding);
    } catch(error) {
      result = catchable.call(binding, error);
    } finally {
      try {
        finalResult = finalizer.call(binding);
      } catch (e){
        finalError = e;
      }
    }

    if (finalError) { throw finalError; }

    return (finalResult === undefined) ? result : finalResult;
  };
} else {
  Ember.tryCatchFinally = function(tryable, catchable, finalizer, binding) {
    var result, finalResult;

    binding = binding || this;

    try {
      result = tryable.call(binding);
    } catch(error) {
      result = catchable.call(binding, error);
    } finally {
      finalResult = finalizer.call(binding);
    }

    return (finalResult === undefined) ? result : finalResult;
  };
}

})();



(function() {
// Ember.tryCatchFinally

/**
  The purpose of the Ember Instrumentation module is
  to provide efficient, general-purpose instrumentation
  for Ember.

  Subscribe to a listener by using `Ember.subscribe`:

  ```javascript
  Ember.subscribe("render", {
    before: function(name, timestamp, payload) {

    },

    after: function(name, timestamp, payload) {

    }
  });
  ```

  If you return a value from the `before` callback, that same
  value will be passed as a fourth parameter to the `after`
  callback.

  Instrument a block of code by using `Ember.instrument`:

  ```javascript
  Ember.instrument("render.handlebars", payload, function() {
    // rendering logic
  }, binding);
  ```

  Event names passed to `Ember.instrument` are namespaced
  by periods, from more general to more specific. Subscribers
  can listen for events by whatever level of granularity they
  are interested in.

  In the above example, the event is `render.handlebars`,
  and the subscriber listened for all events beginning with
  `render`. It would receive callbacks for events named
  `render`, `render.handlebars`, `render.container`, or
  even `render.handlebars.layout`.

  @class Instrumentation
  @namespace Ember
  @static
*/
Ember.Instrumentation = {};

var subscribers = [], cache = {};

var populateListeners = function(name) {
  var listeners = [], subscriber;

  for (var i=0, l=subscribers.length; i<l; i++) {
    subscriber = subscribers[i];
    if (subscriber.regex.test(name)) {
      listeners.push(subscriber.object);
    }
  }

  cache[name] = listeners;
  return listeners;
};

var time = (function() {
  var perf = 'undefined' !== typeof window ? window.performance || {} : {};
	var fn = perf.now || perf.mozNow || perf.webkitNow || perf.msNow || perf.oNow;
	// fn.bind will be available in all the browsers that support the advanced window.performance... ;-)
	return fn ? fn.bind(perf) : function() { return +new Date(); };
})();


Ember.Instrumentation.instrument = function(name, payload, callback, binding) {
  var listeners = cache[name], timeName, ret;

  if (Ember.STRUCTURED_PROFILE) {
    timeName = name + ": " + payload.object;
    console.time(timeName);
  }

  if (!listeners) {
    listeners = populateListeners(name);
  }

  if (listeners.length === 0) {
    ret = callback.call(binding);
    if (Ember.STRUCTURED_PROFILE) { console.timeEnd(timeName); }
    return ret;
  }

  var beforeValues = [], listener, i, l;

  function tryable(){
    for (i=0, l=listeners.length; i<l; i++) {
      listener = listeners[i];
      beforeValues[i] = listener.before(name, time(), payload);
    }

    return callback.call(binding);
  }

  function catchable(e){
    payload = payload || {};
    payload.exception = e;
  }

  function finalizer() {
    for (i=0, l=listeners.length; i<l; i++) {
      listener = listeners[i];
      listener.after(name, time(), payload, beforeValues[i]);
    }

    if (Ember.STRUCTURED_PROFILE) {
      console.timeEnd(timeName);
    }
  }

  return Ember.tryCatchFinally(tryable, catchable, finalizer);
};

Ember.Instrumentation.subscribe = function(pattern, object) {
  var paths = pattern.split("."), path, regex = [];

  for (var i=0, l=paths.length; i<l; i++) {
    path = paths[i];
    if (path === "*") {
      regex.push("[^\\.]*");
    } else {
      regex.push(path);
    }
  }

  regex = regex.join("\\.");
  regex = regex + "(\\..*)?";

  var subscriber = {
    pattern: pattern,
    regex: new RegExp("^" + regex + "$"),
    object: object
  };

  subscribers.push(subscriber);
  cache = {};

  return subscriber;
};

Ember.Instrumentation.unsubscribe = function(subscriber) {
  var index;

  for (var i=0, l=subscribers.length; i<l; i++) {
    if (subscribers[i] === subscriber) {
      index = i;
    }
  }

  subscribers.splice(index, 1);
  cache = {};
};

Ember.Instrumentation.reset = function() {
  subscribers = [];
  cache = {};
};

Ember.instrument = Ember.Instrumentation.instrument;
Ember.subscribe = Ember.Instrumentation.subscribe;

})();



(function() {
/*jshint newcap:false*/

/**
@module ember-metal
*/

// NOTE: There is a bug in jshint that doesn't recognize `Object()` without `new`
// as being ok unless both `newcap:false` and not `use strict`.
// https://github.com/jshint/jshint/issues/392

// Testing this is not ideal, but we want to use native functions
// if available, but not to use versions created by libraries like Prototype
var isNativeFunc = function(func) {
  // This should probably work in all browsers likely to have ES5 array methods
  return func && Function.prototype.toString.call(func).indexOf('[native code]') > -1;
};

// From: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/array/map
var arrayMap = isNativeFunc(Array.prototype.map) ? Array.prototype.map : function(fun /*, thisp */) {
  //"use strict";

  if (this === void 0 || this === null) {
    throw new TypeError();
  }

  var t = Object(this);
  var len = t.length >>> 0;
  if (typeof fun !== "function") {
    throw new TypeError();
  }

  var res = new Array(len);
  var thisp = arguments[1];
  for (var i = 0; i < len; i++) {
    if (i in t) {
      res[i] = fun.call(thisp, t[i], i, t);
    }
  }

  return res;
};

// From: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/array/foreach
var arrayForEach = isNativeFunc(Array.prototype.forEach) ? Array.prototype.forEach : function(fun /*, thisp */) {
  //"use strict";

  if (this === void 0 || this === null) {
    throw new TypeError();
  }

  var t = Object(this);
  var len = t.length >>> 0;
  if (typeof fun !== "function") {
    throw new TypeError();
  }

  var thisp = arguments[1];
  for (var i = 0; i < len; i++) {
    if (i in t) {
      fun.call(thisp, t[i], i, t);
    }
  }
};

var arrayIndexOf = isNativeFunc(Array.prototype.indexOf) ? Array.prototype.indexOf : function (obj, fromIndex) {
  if (fromIndex === null || fromIndex === undefined) { fromIndex = 0; }
  else if (fromIndex < 0) { fromIndex = Math.max(0, this.length + fromIndex); }
  for (var i = fromIndex, j = this.length; i < j; i++) {
    if (this[i] === obj) { return i; }
  }
  return -1;
};

Ember.ArrayPolyfills = {
  map: arrayMap,
  forEach: arrayForEach,
  indexOf: arrayIndexOf
};

var utils = Ember.EnumerableUtils = {
  map: function(obj, callback, thisArg) {
    return obj.map ? obj.map.call(obj, callback, thisArg) : arrayMap.call(obj, callback, thisArg);
  },

  forEach: function(obj, callback, thisArg) {
    return obj.forEach ? obj.forEach.call(obj, callback, thisArg) : arrayForEach.call(obj, callback, thisArg);
  },

  indexOf: function(obj, element, index) {
    return obj.indexOf ? obj.indexOf.call(obj, element, index) : arrayIndexOf.call(obj, element, index);
  },

  indexesOf: function(obj, elements) {
    return elements === undefined ? [] : utils.map(elements, function(item) {
      return utils.indexOf(obj, item);
    });
  },

  addObject: function(array, item) {
    var index = utils.indexOf(array, item);
    if (index === -1) { array.push(item); }
  },

  removeObject: function(array, item) {
    var index = utils.indexOf(array, item);
    if (index !== -1) { array.splice(index, 1); }
  },

  replace: function(array, idx, amt, objects) {
    if (array.replace) {
      return array.replace(idx, amt, objects);
    } else {
      var args = Array.prototype.concat.apply([idx, amt], objects);
      return array.splice.apply(array, args);
    }
  }
};


if (Ember.SHIM_ES5) {
  if (!Array.prototype.map) {
    Array.prototype.map = arrayMap;
  }

  if (!Array.prototype.forEach) {
    Array.prototype.forEach = arrayForEach;
  }

  if (!Array.prototype.indexOf) {
    Array.prototype.indexOf = arrayIndexOf;
  }
}

})();



(function() {
/**
@module ember-metal
*/

/*
  JavaScript (before ES6) does not have a Map implementation. Objects,
  which are often used as dictionaries, may only have Strings as keys.

  Because Ember has a way to get a unique identifier for every object
  via `Ember.guidFor`, we can implement a performant Map with arbitrary
  keys. Because it is commonly used in low-level bookkeeping, Map is
  implemented as a pure JavaScript object for performance.

  This implementation follows the current iteration of the ES6 proposal for
  maps (http://wiki.ecmascript.org/doku.php?id=harmony:simple_maps_and_sets),
  with two exceptions. First, because we need our implementation to be pleasant
  on older browsers, we do not use the `delete` name (using `remove` instead).
  Second, as we do not have the luxury of in-VM iteration, we implement a
  forEach method for iteration.

  Map is mocked out to look like an Ember object, so you can do
  `Ember.Map.create()` for symmetry with other Ember classes.
*/
var guidFor = Ember.guidFor,
    indexOf = Ember.ArrayPolyfills.indexOf;

var copy = function(obj) {
  var output = {};

  for (var prop in obj) {
    if (obj.hasOwnProperty(prop)) { output[prop] = obj[prop]; }
  }

  return output;
};

var copyMap = function(original, newObject) {
  var keys = original.keys.copy(),
      values = copy(original.values);

  newObject.keys = keys;
  newObject.values = values;

  return newObject;
};

/**
  This class is used internally by Ember and Ember Data.
  Please do not use it at this time. We plan to clean it up
  and add many tests soon.

  @class OrderedSet
  @namespace Ember
  @constructor
  @private
*/
var OrderedSet = Ember.OrderedSet = function() {
  this.clear();
};

/**
  @method create
  @static
  @return {Ember.OrderedSet}
*/
OrderedSet.create = function() {
  return new OrderedSet();
};


OrderedSet.prototype = {
  /**
    @method clear
  */
  clear: function() {
    this.presenceSet = {};
    this.list = [];
  },

  /**
    @method add
    @param obj
  */
  add: function(obj) {
    var guid = guidFor(obj),
        presenceSet = this.presenceSet,
        list = this.list;

    if (guid in presenceSet) { return; }

    presenceSet[guid] = true;
    list.push(obj);
  },

  /**
    @method remove
    @param obj
  */
  remove: function(obj) {
    var guid = guidFor(obj),
        presenceSet = this.presenceSet,
        list = this.list;

    delete presenceSet[guid];

    var index = indexOf.call(list, obj);
    if (index > -1) {
      list.splice(index, 1);
    }
  },

  /**
    @method isEmpty
    @return {Boolean}
  */
  isEmpty: function() {
    return this.list.length === 0;
  },

  /**
    @method has
    @param obj
    @return {Boolean}
  */
  has: function(obj) {
    var guid = guidFor(obj),
        presenceSet = this.presenceSet;

    return guid in presenceSet;
  },

  /**
    @method forEach
    @param {Function} function
    @param target
  */
  forEach: function(fn, self) {
    // allow mutation during iteration
    var list = this.list.slice();

    for (var i = 0, j = list.length; i < j; i++) {
      fn.call(self, list[i]);
    }
  },

  /**
    @method toArray
    @return {Array}
  */
  toArray: function() {
    return this.list.slice();
  },

  /**
    @method copy
    @return {Ember.OrderedSet}
  */
  copy: function() {
    var set = new OrderedSet();

    set.presenceSet = copy(this.presenceSet);
    set.list = this.list.slice();

    return set;
  }
};

/**
  A Map stores values indexed by keys. Unlike JavaScript's
  default Objects, the keys of a Map can be any JavaScript
  object.

  Internally, a Map has two data structures:

  1. `keys`: an OrderedSet of all of the existing keys
  2. `values`: a JavaScript Object indexed by the `Ember.guidFor(key)`

  When a key/value pair is added for the first time, we
  add the key to the `keys` OrderedSet, and create or
  replace an entry in `values`. When an entry is deleted,
  we delete its entry in `keys` and `values`.

  @class Map
  @namespace Ember
  @private
  @constructor
*/
var Map = Ember.Map = function() {
  this.keys = Ember.OrderedSet.create();
  this.values = {};
};

/**
  @method create
  @static
*/
Map.create = function() {
  return new Map();
};

Map.prototype = {
  /**
    Retrieve the value associated with a given key.

    @method get
    @param {anything} key
    @return {anything} the value associated with the key, or `undefined`
  */
  get: function(key) {
    var values = this.values,
        guid = guidFor(key);

    return values[guid];
  },

  /**
    Adds a value to the map. If a value for the given key has already been
    provided, the new value will replace the old value.

    @method set
    @param {anything} key
    @param {anything} value
  */
  set: function(key, value) {
    var keys = this.keys,
        values = this.values,
        guid = guidFor(key);

    keys.add(key);
    values[guid] = value;
  },

  /**
    Removes a value from the map for an associated key.

    @method remove
    @param {anything} key
    @return {Boolean} true if an item was removed, false otherwise
  */
  remove: function(key) {
    // don't use ES6 "delete" because it will be annoying
    // to use in browsers that are not ES6 friendly;
    var keys = this.keys,
        values = this.values,
        guid = guidFor(key),
        value;

    if (values.hasOwnProperty(guid)) {
      keys.remove(key);
      value = values[guid];
      delete values[guid];
      return true;
    } else {
      return false;
    }
  },

  /**
    Check whether a key is present.

    @method has
    @param {anything} key
    @return {Boolean} true if the item was present, false otherwise
  */
  has: function(key) {
    var values = this.values,
        guid = guidFor(key);

    return values.hasOwnProperty(guid);
  },

  /**
    Iterate over all the keys and values. Calls the function once
    for each key, passing in the key and value, in that order.

    The keys are guaranteed to be iterated over in insertion order.

    @method forEach
    @param {Function} callback
    @param {anything} self if passed, the `this` value inside the
      callback. By default, `this` is the map.
  */
  forEach: function(callback, self) {
    var keys = this.keys,
        values = this.values;

    keys.forEach(function(key) {
      var guid = guidFor(key);
      callback.call(self, key, values[guid]);
    });
  },

  /**
    @method copy
    @return {Ember.Map}
  */
  copy: function() {
    return copyMap(this, new Map());
  }
};

/**
  @class MapWithDefault
  @namespace Ember
  @extends Ember.Map
  @private
  @constructor
  @param [options]
    @param {anything} [options.defaultValue]
*/
var MapWithDefault = Ember.MapWithDefault = function(options) {
  Map.call(this);
  this.defaultValue = options.defaultValue;
};

/**
  @method create
  @static
  @param [options]
    @param {anything} [options.defaultValue]
  @return {Ember.MapWithDefault|Ember.Map} If options are passed, returns 
    `Ember.MapWithDefault` otherwise returns `Ember.Map`
*/
MapWithDefault.create = function(options) {
  if (options) {
    return new MapWithDefault(options);
  } else {
    return new Map();
  }
};

MapWithDefault.prototype = Ember.create(Map.prototype);

/**
  Retrieve the value associated with a given key.

  @method get
  @param {anything} key
  @return {anything} the value associated with the key, or the default value
*/
MapWithDefault.prototype.get = function(key) {
  var hasValue = this.has(key);

  if (hasValue) {
    return Map.prototype.get.call(this, key);
  } else {
    var defaultValue = this.defaultValue(key);
    this.set(key, defaultValue);
    return defaultValue;
  }
};

/**
  @method copy
  @return {Ember.MapWithDefault}
*/
MapWithDefault.prototype.copy = function() {
  return copyMap(this, new MapWithDefault({
    defaultValue: this.defaultValue
  }));
};

})();



(function() {
/**
@module ember-metal
*/

var META_KEY = Ember.META_KEY, get, set;

var MANDATORY_SETTER = Ember.ENV.MANDATORY_SETTER;

var IS_GLOBAL = /^([A-Z$]|([0-9][A-Z$]))/;
var IS_GLOBAL_PATH = /^([A-Z$]|([0-9][A-Z$])).*[\.\*]/;
var HAS_THIS  = /^this[\.\*]/;
var FIRST_KEY = /^([^\.\*]+)/;

// ..........................................................
// GET AND SET
//
// If we are on a platform that supports accessors we can get use those.
// Otherwise simulate accessors by looking up the property directly on the
// object.

/**
  Gets the value of a property on an object. If the property is computed,
  the function will be invoked. If the property is not defined but the
  object implements the `unknownProperty` method then that will be invoked.

  If you plan to run on IE8 and older browsers then you should use this
  method anytime you want to retrieve a property on an object that you don't
  know for sure is private. (Properties beginning with an underscore '_' 
  are considered private.)

  On all newer browsers, you only need to use this method to retrieve
  properties if the property might not be defined on the object and you want
  to respect the `unknownProperty` handler. Otherwise you can ignore this
  method.

  Note that if the object itself is `undefined`, this method will throw
  an error.

  @method get
  @for Ember
  @param {Object} obj The object to retrieve from.
  @param {String} keyName The property key to retrieve
  @return {Object} the property value or `null`.
*/
get = function get(obj, keyName) {
  // Helpers that operate with 'this' within an #each
  if (keyName === '') {
    return obj;
  }

  if (!keyName && 'string'===typeof obj) {
    keyName = obj;
    obj = null;
  }

  if (!obj || keyName.indexOf('.') !== -1) {
    Ember.assert("Cannot call get with '"+ keyName +"' on an undefined object.", obj !== undefined);
    return getPath(obj, keyName);
  }

  Ember.assert("You need to provide an object and key to `get`.", !!obj && keyName);

  var meta = obj[META_KEY], desc = meta && meta.descs[keyName], ret;
  if (desc) {
    return desc.get(obj, keyName);
  } else {
    if (MANDATORY_SETTER && meta && meta.watching[keyName] > 0) {
      ret = meta.values[keyName];
    } else {
      ret = obj[keyName];
    }

    if (ret === undefined &&
        'object' === typeof obj && !(keyName in obj) && 'function' === typeof obj.unknownProperty) {
      return obj.unknownProperty(keyName);
    }

    return ret;
  }
};

/**
  Sets the value of a property on an object, respecting computed properties
  and notifying observers and other listeners of the change. If the
  property is not defined but the object implements the `unknownProperty`
  method then that will be invoked as well.

  If you plan to run on IE8 and older browsers then you should use this
  method anytime you want to set a property on an object that you don't
  know for sure is private. (Properties beginning with an underscore '_' 
  are considered private.)

  On all newer browsers, you only need to use this method to set
  properties if the property might not be defined on the object and you want
  to respect the `unknownProperty` handler. Otherwise you can ignore this
  method.

  @method set
  @for Ember
  @param {Object} obj The object to modify.
  @param {String} keyName The property key to set
  @param {Object} value The value to set
  @return {Object} the passed value.
*/
set = function set(obj, keyName, value, tolerant) {
  if (typeof obj === 'string') {
    Ember.assert("Path '" + obj + "' must be global if no obj is given.", IS_GLOBAL.test(obj));
    value = keyName;
    keyName = obj;
    obj = null;
  }

  if (!obj || keyName.indexOf('.') !== -1) {
    return setPath(obj, keyName, value, tolerant);
  }

  Ember.assert("You need to provide an object and key to `set`.", !!obj && keyName !== undefined);
  Ember.assert('calling set on destroyed object', !obj.isDestroyed);

  var meta = obj[META_KEY], desc = meta && meta.descs[keyName],
      isUnknown, currentValue;
  if (desc) {
    desc.set(obj, keyName, value);
  } else {
    isUnknown = 'object' === typeof obj && !(keyName in obj);

    // setUnknownProperty is called if `obj` is an object,
    // the property does not already exist, and the
    // `setUnknownProperty` method exists on the object
    if (isUnknown && 'function' === typeof obj.setUnknownProperty) {
      obj.setUnknownProperty(keyName, value);
    } else if (meta && meta.watching[keyName] > 0) {
      if (MANDATORY_SETTER) {
        currentValue = meta.values[keyName];
      } else {
        currentValue = obj[keyName];
      }
      // only trigger a change if the value has changed
      if (value !== currentValue) {
        Ember.propertyWillChange(obj, keyName);
        if (MANDATORY_SETTER) {
          if (currentValue === undefined && !(keyName in obj)) {
            Ember.defineProperty(obj, keyName, null, value); // setup mandatory setter
          } else {
            meta.values[keyName] = value;
          }
        } else {
          obj[keyName] = value;
        }
        Ember.propertyDidChange(obj, keyName);
      }
    } else {
      obj[keyName] = value;
    }
  }
  return value;
};

// Currently used only by Ember Data tests
if (Ember.config.overrideAccessors) {
  Ember.get = get;
  Ember.set = set;
  Ember.config.overrideAccessors();
  get = Ember.get;
  set = Ember.set;
}

function firstKey(path) {
  return path.match(FIRST_KEY)[0];
}

// assumes path is already normalized
function normalizeTuple(target, path) {
  var hasThis  = HAS_THIS.test(path),
      isGlobal = !hasThis && IS_GLOBAL_PATH.test(path),
      key;

  if (!target || isGlobal) target = Ember.lookup;
  if (hasThis) path = path.slice(5);

  if (target === Ember.lookup) {
    key = firstKey(path);
    target = get(target, key);
    path   = path.slice(key.length+1);
  }

  // must return some kind of path to be valid else other things will break.
  if (!path || path.length===0) throw new Error('Invalid Path');

  return [ target, path ];
}

function getPath(root, path) {
  var hasThis, parts, tuple, idx, len;

  // If there is no root and path is a key name, return that
  // property from the global object.
  // E.g. get('Ember') -> Ember
  if (root === null && path.indexOf('.') === -1) { return get(Ember.lookup, path); }

  // detect complicated paths and normalize them
  hasThis  = HAS_THIS.test(path);

  if (!root || hasThis) {
    tuple = normalizeTuple(root, path);
    root = tuple[0];
    path = tuple[1];
    tuple.length = 0;
  }

  parts = path.split(".");
  len = parts.length;
  for (idx=0; root && idx<len; idx++) {
    root = get(root, parts[idx], true);
    if (root && root.isDestroyed) { return undefined; }
  }
  return root;
}

function setPath(root, path, value, tolerant) {
  var keyName;

  // get the last part of the path
  keyName = path.slice(path.lastIndexOf('.') + 1);

  // get the first part of the part
  path    = path.slice(0, path.length-(keyName.length+1));

  // unless the path is this, look up the first part to
  // get the root
  if (path !== 'this') {
    root = getPath(root, path);
  }

  if (!keyName || keyName.length === 0) {
    throw new Error('You passed an empty path');
  }

  if (!root) {
    if (tolerant) { return; }
    else { throw new Error('Object in path '+path+' could not be found or was destroyed.'); }
  }

  return set(root, keyName, value);
}

/**
  @private

  Normalizes a target/path pair to reflect that actual target/path that should
  be observed, etc. This takes into account passing in global property
  paths (i.e. a path beginning with a captial letter not defined on the
  target) and * separators.

  @method normalizeTuple
  @for Ember
  @param {Object} target The current target. May be `null`.
  @param {String} path A path on the target or a global property path.
  @return {Array} a temporary array with the normalized target/path pair.
*/
Ember.normalizeTuple = function(target, path) {
  return normalizeTuple(target, path);
};

Ember.getWithDefault = function(root, key, defaultValue) {
  var value = get(root, key);

  if (value === undefined) { return defaultValue; }
  return value;
};


Ember.get = get;
Ember.getPath = Ember.deprecateFunc('getPath is deprecated since get now supports paths', Ember.get);

Ember.set = set;
Ember.setPath = Ember.deprecateFunc('setPath is deprecated since set now supports paths', Ember.set);

/**
  Error-tolerant form of `Ember.set`. Will not blow up if any part of the
  chain is `undefined`, `null`, or destroyed.

  This is primarily used when syncing bindings, which may try to update after
  an object has been destroyed.

  @method trySet
  @for Ember
  @param {Object} obj The object to modify.
  @param {String} keyName The property key to set
  @param {Object} value The value to set
*/
Ember.trySet = function(root, path, value) {
  return set(root, path, value, true);
};
Ember.trySetPath = Ember.deprecateFunc('trySetPath has been renamed to trySet', Ember.trySet);

/**
  Returns true if the provided path is global (e.g., `MyApp.fooController.bar`)
  instead of local (`foo.bar.baz`).

  @method isGlobalPath
  @for Ember
  @private
  @param {String} path
  @return Boolean
*/
Ember.isGlobalPath = function(path) {
  return IS_GLOBAL.test(path);
};


})();



(function() {
/**
@module ember-metal
*/

var GUID_KEY = Ember.GUID_KEY,
    META_KEY = Ember.META_KEY,
    EMPTY_META = Ember.EMPTY_META,
    metaFor = Ember.meta,
    o_create = Ember.create,
    objectDefineProperty = Ember.platform.defineProperty;

var MANDATORY_SETTER = Ember.ENV.MANDATORY_SETTER;

// ..........................................................
// DESCRIPTOR
//

/**
  Objects of this type can implement an interface to responds requests to
  get and set. The default implementation handles simple properties.

  You generally won't need to create or subclass this directly.

  @class Descriptor
  @namespace Ember
  @private
  @constructor
*/
var Descriptor = Ember.Descriptor = function() {};

// ..........................................................
// DEFINING PROPERTIES API
//

/**
  @private

  NOTE: This is a low-level method used by other parts of the API. You almost
  never want to call this method directly. Instead you should use
  `Ember.mixin()` to define new properties.

  Defines a property on an object. This method works much like the ES5
  `Object.defineProperty()` method except that it can also accept computed
  properties and other special descriptors.

  Normally this method takes only three parameters. However if you pass an
  instance of `Ember.Descriptor` as the third param then you can pass an
  optional value as the fourth parameter. This is often more efficient than
  creating new descriptor hashes for each property.

  ## Examples

  ```javascript
  // ES5 compatible mode
  Ember.defineProperty(contact, 'firstName', {
    writable: true,
    configurable: false,
    enumerable: true,
    value: 'Charles'
  });

  // define a simple property
  Ember.defineProperty(contact, 'lastName', undefined, 'Jolley');

  // define a computed property
  Ember.defineProperty(contact, 'fullName', Ember.computed(function() {
    return this.firstName+' '+this.lastName;
  }).property('firstName', 'lastName'));
  ```

  @method defineProperty
  @for Ember
  @param {Object} obj the object to define this property on. This may be a prototype.
  @param {String} keyName the name of the property
  @param {Ember.Descriptor} [desc] an instance of `Ember.Descriptor` (typically a
    computed property) or an ES5 descriptor.
    You must provide this or `data` but not both.
  @param {anything} [data] something other than a descriptor, that will
    become the explicit value of this property.
*/
Ember.defineProperty = function(obj, keyName, desc, data, meta) {
  var descs, existingDesc, watching, value;

  if (!meta) meta = metaFor(obj);
  descs = meta.descs;
  existingDesc = meta.descs[keyName];
  watching = meta.watching[keyName] > 0;

  if (existingDesc instanceof Ember.Descriptor) {
    existingDesc.teardown(obj, keyName);
  }

  if (desc instanceof Ember.Descriptor) {
    value = desc;

    descs[keyName] = desc;
    if (MANDATORY_SETTER && watching) {
      objectDefineProperty(obj, keyName, {
        configurable: true,
        enumerable: true,
        writable: true,
        value: undefined // make enumerable
      });
    } else {
      obj[keyName] = undefined; // make enumerable
    }
    desc.setup(obj, keyName);
  } else {
    descs[keyName] = undefined; // shadow descriptor in proto
    if (desc == null) {
      value = data;

      if (MANDATORY_SETTER && watching) {
        meta.values[keyName] = data;
        objectDefineProperty(obj, keyName, {
          configurable: true,
          enumerable: true,
          set: function() {
            Ember.assert('Must use Ember.set() to access this property', false);
          },
          get: function() {
            var meta = this[META_KEY];
            return meta && meta.values[keyName];
          }
        });
      } else {
        obj[keyName] = data;
      }
    } else {
      value = desc;

      // compatibility with ES5
      objectDefineProperty(obj, keyName, desc);
    }
  }

  // if key is being watched, override chains that
  // were initialized with the prototype
  if (watching) { Ember.overrideChains(obj, keyName, meta); }

  // The `value` passed to the `didDefineProperty` hook is
  // either the descriptor or data, whichever was passed.
  if (obj.didDefineProperty) { obj.didDefineProperty(obj, keyName, value); }

  return this;
};


})();



(function() {
// Ember.tryFinally
/**
@module ember-metal
*/

var AFTER_OBSERVERS = ':change';
var BEFORE_OBSERVERS = ':before';

var guidFor = Ember.guidFor;

var deferred = 0;

/*
  this.observerSet = {
    [senderGuid]: { // variable name: `keySet`
      [keyName]: listIndex
    }
  },
  this.observers = [
    {
      sender: obj,
      keyName: keyName,
      eventName: eventName,
      listeners: [
        [target, method, onceFlag, suspendedFlag]
      ]
    },
    ...
  ]
*/
function ObserverSet() {
  this.clear();
}

ObserverSet.prototype.add = function(sender, keyName, eventName) {
  var observerSet = this.observerSet,
      observers = this.observers,
      senderGuid = Ember.guidFor(sender),
      keySet = observerSet[senderGuid],
      index;

  if (!keySet) {
    observerSet[senderGuid] = keySet = {};
  }
  index = keySet[keyName];
  if (index === undefined) {
    index = observers.push({
      sender: sender,
      keyName: keyName,
      eventName: eventName,
      listeners: []
    }) - 1;
    keySet[keyName] = index;
  }
  return observers[index].listeners;
};

ObserverSet.prototype.flush = function() {
  var observers = this.observers, i, len, observer, sender;
  this.clear();
  for (i=0, len=observers.length; i < len; ++i) {
    observer = observers[i];
    sender = observer.sender;
    if (sender.isDestroying || sender.isDestroyed) { continue; }
    Ember.sendEvent(sender, observer.eventName, [sender, observer.keyName], observer.listeners);
  }
};

ObserverSet.prototype.clear = function() {
  this.observerSet = {};
  this.observers = [];
};

var beforeObserverSet = new ObserverSet(), observerSet = new ObserverSet();

/**
  @method beginPropertyChanges
  @chainable
*/
Ember.beginPropertyChanges = function() {
  deferred++;
};

/**
  @method endPropertyChanges
*/
Ember.endPropertyChanges = function() {
  deferred--;
  if (deferred<=0) {
    beforeObserverSet.clear();
    observerSet.flush();
  }
};

/**
  Make a series of property changes together in an
  exception-safe way.

  ```javascript
  Ember.changeProperties(function() {
    obj1.set('foo', mayBlowUpWhenSet);
    obj2.set('bar', baz);
  });
  ```

  @method changeProperties
  @param {Function} callback
  @param [binding]
*/
Ember.changeProperties = function(cb, binding){
  Ember.beginPropertyChanges();
  Ember.tryFinally(cb, Ember.endPropertyChanges, binding);
};

/**
  Set a list of properties on an object. These properties are set inside
  a single `beginPropertyChanges` and `endPropertyChanges` batch, so
  observers will be buffered.

  @method setProperties
  @param target
  @param {Hash} properties
  @return target
*/
Ember.setProperties = function(self, hash) {
  Ember.changeProperties(function(){
    for(var prop in hash) {
      if (hash.hasOwnProperty(prop)) Ember.set(self, prop, hash[prop]);
    }
  });
  return self;
};


function changeEvent(keyName) {
  return keyName+AFTER_OBSERVERS;
}

function beforeEvent(keyName) {
  return keyName+BEFORE_OBSERVERS;
}

/**
  @method addObserver
  @param obj
  @param {String} path
  @param {Object|Function} targetOrMethod
  @param {Function|String} [method]
*/
Ember.addObserver = function(obj, path, target, method) {
  Ember.addListener(obj, changeEvent(path), target, method);
  Ember.watch(obj, path);
  return this;
};

Ember.observersFor = function(obj, path) {
  return Ember.listenersFor(obj, changeEvent(path));
};

/**
  @method removeObserver
  @param obj
  @param {String} path
  @param {Object|Function} targetOrMethod
  @param {Function|String} [method]
*/
Ember.removeObserver = function(obj, path, target, method) {
  Ember.unwatch(obj, path);
  Ember.removeListener(obj, changeEvent(path), target, method);
  return this;
};

/**
  @method addBeforeObserver
  @param obj
  @param {String} path
  @param {Object|Function} targetOrMethod
  @param {Function|String} [method]
*/
Ember.addBeforeObserver = function(obj, path, target, method) {
  Ember.addListener(obj, beforeEvent(path), target, method);
  Ember.watch(obj, path);
  return this;
};

// Suspend observer during callback.
//
// This should only be used by the target of the observer
// while it is setting the observed path.
Ember._suspendBeforeObserver = function(obj, path, target, method, callback) {
  return Ember._suspendListener(obj, beforeEvent(path), target, method, callback);
};

Ember._suspendObserver = function(obj, path, target, method, callback) {
  return Ember._suspendListener(obj, changeEvent(path), target, method, callback);
};

var map = Ember.ArrayPolyfills.map;

Ember._suspendBeforeObservers = function(obj, paths, target, method, callback) {
  var events = map.call(paths, beforeEvent);
  return Ember._suspendListeners(obj, events, target, method, callback);
};

Ember._suspendObservers = function(obj, paths, target, method, callback) {
  var events = map.call(paths, changeEvent);
  return Ember._suspendListeners(obj, events, target, method, callback);
};

Ember.beforeObserversFor = function(obj, path) {
  return Ember.listenersFor(obj, beforeEvent(path));
};

/**
  @method removeBeforeObserver
  @param obj
  @param {String} path
  @param {Object|Function} targetOrMethod
  @param {Function|String} [method]
*/
Ember.removeBeforeObserver = function(obj, path, target, method) {
  Ember.unwatch(obj, path);
  Ember.removeListener(obj, beforeEvent(path), target, method);
  return this;
};

Ember.notifyBeforeObservers = function(obj, keyName) {
  if (obj.isDestroying) { return; }

  var eventName = beforeEvent(keyName), listeners, listenersDiff;
  if (deferred) {
    listeners = beforeObserverSet.add(obj, keyName, eventName);
    listenersDiff = Ember.listenersDiff(obj, eventName, listeners);
    Ember.sendEvent(obj, eventName, [obj, keyName], listenersDiff);
  } else {
    Ember.sendEvent(obj, eventName, [obj, keyName]);
  }
};

Ember.notifyObservers = function(obj, keyName) {
  if (obj.isDestroying) { return; }

  var eventName = changeEvent(keyName), listeners;
  if (deferred) {
    listeners = observerSet.add(obj, keyName, eventName);
    Ember.listenersUnion(obj, eventName, listeners);
  } else {
    Ember.sendEvent(obj, eventName, [obj, keyName]);
  }
};

})();



(function() {
/**
@module ember-metal
*/

var guidFor = Ember.guidFor, // utils.js
    metaFor = Ember.meta, // utils.js
    get = Ember.get, // accessors.js
    set = Ember.set, // accessors.js
    normalizeTuple = Ember.normalizeTuple, // accessors.js
    GUID_KEY = Ember.GUID_KEY, // utils.js
    META_KEY = Ember.META_KEY, // utils.js
    // circular reference observer depends on Ember.watch
    // we should move change events to this file or its own property_events.js
    notifyObservers = Ember.notifyObservers, // observer.js
    forEach = Ember.ArrayPolyfills.forEach, // array.js
    FIRST_KEY = /^([^\.\*]+)/,
    IS_PATH = /[\.\*]/;

var MANDATORY_SETTER = Ember.ENV.MANDATORY_SETTER,
o_defineProperty = Ember.platform.defineProperty;

function firstKey(path) {
  return path.match(FIRST_KEY)[0];
}

// returns true if the passed path is just a keyName
function isKeyName(path) {
  return path==='*' || !IS_PATH.test(path);
}

// ..........................................................
// DEPENDENT KEYS
//

function iterDeps(method, obj, depKey, seen, meta) {

  var guid = guidFor(obj);
  if (!seen[guid]) seen[guid] = {};
  if (seen[guid][depKey]) return;
  seen[guid][depKey] = true;

  var deps = meta.deps;
  deps = deps && deps[depKey];
  if (deps) {
    for(var key in deps) {
      var desc = meta.descs[key];
      if (desc && desc._suspended === obj) continue;
      method(obj, key);
    }
  }
}


var WILL_SEEN, DID_SEEN;

// called whenever a property is about to change to clear the cache of any dependent keys (and notify those properties of changes, etc...)
function dependentKeysWillChange(obj, depKey, meta) {
  if (obj.isDestroying) { return; }

  var seen = WILL_SEEN, top = !seen;
  if (top) { seen = WILL_SEEN = {}; }
  iterDeps(propertyWillChange, obj, depKey, seen, meta);
  if (top) { WILL_SEEN = null; }
}

// called whenever a property has just changed to update dependent keys
function dependentKeysDidChange(obj, depKey, meta) {
  if (obj.isDestroying) { return; }

  var seen = DID_SEEN, top = !seen;
  if (top) { seen = DID_SEEN = {}; }
  iterDeps(propertyDidChange, obj, depKey, seen, meta);
  if (top) { DID_SEEN = null; }
}

// ..........................................................
// CHAIN
//

function addChainWatcher(obj, keyName, node) {
  if (!obj || ('object' !== typeof obj)) { return; } // nothing to do

  var m = metaFor(obj), nodes = m.chainWatchers;

  if (!m.hasOwnProperty('chainWatchers')) {
    nodes = m.chainWatchers = {};
  }

  if (!nodes[keyName]) { nodes[keyName] = []; }
  nodes[keyName].push(node);
  Ember.watch(obj, keyName);
}

function removeChainWatcher(obj, keyName, node) {
  if (!obj || 'object' !== typeof obj) { return; } // nothing to do

  var m = metaFor(obj, false);
  if (!m.hasOwnProperty('chainWatchers')) { return; } // nothing to do

  var nodes = m.chainWatchers;

  if (nodes[keyName]) {
    nodes = nodes[keyName];
    for (var i = 0, l = nodes.length; i < l; i++) {
      if (nodes[i] === node) { nodes.splice(i, 1); }
    }
  }
  Ember.unwatch(obj, keyName);
}

var pendingQueue = [];

// attempts to add the pendingQueue chains again. If some of them end up
// back in the queue and reschedule is true, schedules a timeout to try
// again.
function flushPendingChains() {
  if (pendingQueue.length === 0) { return; } // nothing to do

  var queue = pendingQueue;
  pendingQueue = [];

  forEach.call(queue, function(q) { q[0].add(q[1]); });

  Ember.warn('Watching an undefined global, Ember expects watched globals to be setup by the time the run loop is flushed, check for typos', pendingQueue.length === 0);
}

function isProto(pvalue) {
  return metaFor(pvalue, false).proto === pvalue;
}

// A ChainNode watches a single key on an object. If you provide a starting
// value for the key then the node won't actually watch it. For a root node
// pass null for parent and key and object for value.
var ChainNode = function(parent, key, value) {
  var obj;
  this._parent = parent;
  this._key    = key;

  // _watching is true when calling get(this._parent, this._key) will
  // return the value of this node.
  //
  // It is false for the root of a chain (because we have no parent)
  // and for global paths (because the parent node is the object with
  // the observer on it)
  this._watching = value===undefined;

  this._value  = value;
  this._paths = {};
  if (this._watching) {
    this._object = parent.value();
    if (this._object) { addChainWatcher(this._object, this._key, this); }
  }

  // Special-case: the EachProxy relies on immediate evaluation to
  // establish its observers.
  //
  // TODO: Replace this with an efficient callback that the EachProxy
  // can implement.
  if (this._parent && this._parent._key === '@each') {
    this.value();
  }
};

var ChainNodePrototype = ChainNode.prototype;

ChainNodePrototype.value = function() {
  if (this._value === undefined && this._watching) {
    var obj = this._parent.value();
    this._value = (obj && !isProto(obj)) ? get(obj, this._key) : undefined;
  }
  return this._value;
};

ChainNodePrototype.destroy = function() {
  if (this._watching) {
    var obj = this._object;
    if (obj) { removeChainWatcher(obj, this._key, this); }
    this._watching = false; // so future calls do nothing
  }
};

// copies a top level object only
ChainNodePrototype.copy = function(obj) {
  var ret = new ChainNode(null, null, obj),
      paths = this._paths, path;
  for (path in paths) {
    if (paths[path] <= 0) { continue; } // this check will also catch non-number vals.
    ret.add(path);
  }
  return ret;
};

// called on the root node of a chain to setup watchers on the specified
// path.
ChainNodePrototype.add = function(path) {
  var obj, tuple, key, src, paths;

  paths = this._paths;
  paths[path] = (paths[path] || 0) + 1;

  obj = this.value();
  tuple = normalizeTuple(obj, path);

  // the path was a local path
  if (tuple[0] && tuple[0] === obj) {
    path = tuple[1];
    key  = firstKey(path);
    path = path.slice(key.length+1);

  // global path, but object does not exist yet.
  // put into a queue and try to connect later.
  } else if (!tuple[0]) {
    pendingQueue.push([this, path]);
    tuple.length = 0;
    return;

  // global path, and object already exists
  } else {
    src  = tuple[0];
    key  = path.slice(0, 0-(tuple[1].length+1));
    path = tuple[1];
  }

  tuple.length = 0;
  this.chain(key, path, src);
};

// called on the root node of a chain to teardown watcher on the specified
// path
ChainNodePrototype.remove = function(path) {
  var obj, tuple, key, src, paths;

  paths = this._paths;
  if (paths[path] > 0) { paths[path]--; }

  obj = this.value();
  tuple = normalizeTuple(obj, path);
  if (tuple[0] === obj) {
    path = tuple[1];
    key  = firstKey(path);
    path = path.slice(key.length+1);
  } else {
    src  = tuple[0];
    key  = path.slice(0, 0-(tuple[1].length+1));
    path = tuple[1];
  }

  tuple.length = 0;
  this.unchain(key, path);
};

ChainNodePrototype.count = 0;

ChainNodePrototype.chain = function(key, path, src) {
  var chains = this._chains, node;
  if (!chains) { chains = this._chains = {}; }

  node = chains[key];
  if (!node) { node = chains[key] = new ChainNode(this, key, src); }
  node.count++; // count chains...

  // chain rest of path if there is one
  if (path && path.length>0) {
    key = firstKey(path);
    path = path.slice(key.length+1);
    node.chain(key, path); // NOTE: no src means it will observe changes...
  }
};

ChainNodePrototype.unchain = function(key, path) {
  var chains = this._chains, node = chains[key];

  // unchain rest of path first...
  if (path && path.length>1) {
    key  = firstKey(path);
    path = path.slice(key.length+1);
    node.unchain(key, path);
  }

  // delete node if needed.
  node.count--;
  if (node.count<=0) {
    delete chains[node._key];
    node.destroy();
  }

};

ChainNodePrototype.willChange = function() {
  var chains = this._chains;
  if (chains) {
    for(var key in chains) {
      if (!chains.hasOwnProperty(key)) { continue; }
      chains[key].willChange();
    }
  }

  if (this._parent) { this._parent.chainWillChange(this, this._key, 1); }
};

ChainNodePrototype.chainWillChange = function(chain, path, depth) {
  if (this._key) { path = this._key + '.' + path; }

  if (this._parent) {
    this._parent.chainWillChange(this, path, depth+1);
  } else {
    if (depth > 1) { Ember.propertyWillChange(this.value(), path); }
    path = 'this.' + path;
    if (this._paths[path] > 0) { Ember.propertyWillChange(this.value(), path); }
  }
};

ChainNodePrototype.chainDidChange = function(chain, path, depth) {
  if (this._key) { path = this._key + '.' + path; }
  if (this._parent) {
    this._parent.chainDidChange(this, path, depth+1);
  } else {
    if (depth > 1) { Ember.propertyDidChange(this.value(), path); }
    path = 'this.' + path;
    if (this._paths[path] > 0) { Ember.propertyDidChange(this.value(), path); }
  }
};

ChainNodePrototype.didChange = function(suppressEvent) {
  // invalidate my own value first.
  if (this._watching) {
    var obj = this._parent.value();
    if (obj !== this._object) {
      removeChainWatcher(this._object, this._key, this);
      this._object = obj;
      addChainWatcher(obj, this._key, this);
    }
    this._value  = undefined;

    // Special-case: the EachProxy relies on immediate evaluation to
    // establish its observers.
    if (this._parent && this._parent._key === '@each')
      this.value();
  }

  // then notify chains...
  var chains = this._chains;
  if (chains) {
    for(var key in chains) {
      if (!chains.hasOwnProperty(key)) { continue; }
      chains[key].didChange(suppressEvent);
    }
  }

  if (suppressEvent) { return; }

  // and finally tell parent about my path changing...
  if (this._parent) { this._parent.chainDidChange(this, this._key, 1); }
};

// get the chains for the current object. If the current object has
// chains inherited from the proto they will be cloned and reconfigured for
// the current object.
function chainsFor(obj) {
  var m = metaFor(obj), ret = m.chains;
  if (!ret) {
    ret = m.chains = new ChainNode(null, null, obj);
  } else if (ret.value() !== obj) {
    ret = m.chains = ret.copy(obj);
  }
  return ret;
}

Ember.overrideChains = function(obj, keyName, m) {
  chainsDidChange(obj, keyName, m, true);
};

function chainsWillChange(obj, keyName, m, arg) {
  if (!m.hasOwnProperty('chainWatchers')) { return; } // nothing to do

  var nodes = m.chainWatchers;

  nodes = nodes[keyName];
  if (!nodes) { return; }

  for(var i = 0, l = nodes.length; i < l; i++) {
    nodes[i].willChange(arg);
  }
}

function chainsDidChange(obj, keyName, m, arg) {
  if (!m.hasOwnProperty('chainWatchers')) { return; } // nothing to do

  var nodes = m.chainWatchers;

  nodes = nodes[keyName];
  if (!nodes) { return; }

  // looping in reverse because the chainWatchers array can be modified inside didChange
  for (var i = nodes.length - 1; i >= 0; i--) {
    nodes[i].didChange(arg);
  }
}

// ..........................................................
// WATCH
//

/**
  @private

  Starts watching a property on an object. Whenever the property changes,
  invokes `Ember.propertyWillChange` and `Ember.propertyDidChange`. This is the
  primitive used by observers and dependent keys; usually you will never call
  this method directly but instead use higher level methods like
  `Ember.addObserver()`

  @method watch
  @for Ember
  @param obj
  @param {String} keyName
*/
Ember.watch = function(obj, keyName) {
  // can't watch length on Array - it is special...
  if (keyName === 'length' && Ember.typeOf(obj) === 'array') { return this; }

  var m = metaFor(obj), watching = m.watching, desc;

  // activate watching first time
  if (!watching[keyName]) {
    watching[keyName] = 1;
    if (isKeyName(keyName)) {
      desc = m.descs[keyName];
      if (desc && desc.willWatch) { desc.willWatch(obj, keyName); }

      if ('function' === typeof obj.willWatchProperty) {
        obj.willWatchProperty(keyName);
      }

      if (MANDATORY_SETTER && keyName in obj) {
        m.values[keyName] = obj[keyName];
        o_defineProperty(obj, keyName, {
          configurable: true,
          enumerable: true,
          set: function() {
            Ember.assert('Must use Ember.set() to access this property', false);
          },
          get: function() {
            var meta = this[META_KEY];
            return meta && meta.values[keyName];
          }
        });
      }
    } else {
      chainsFor(obj).add(keyName);
    }

  }  else {
    watching[keyName] = (watching[keyName] || 0) + 1;
  }
  return this;
};

Ember.isWatching = function isWatching(obj, key) {
  var meta = obj[META_KEY];
  return (meta && meta.watching[key]) > 0;
};

Ember.watch.flushPending = flushPendingChains;

Ember.unwatch = function(obj, keyName) {
  // can't watch length on Array - it is special...
  if (keyName === 'length' && Ember.typeOf(obj) === 'array') { return this; }

  var m = metaFor(obj), watching = m.watching, desc;

  if (watching[keyName] === 1) {
    watching[keyName] = 0;

    if (isKeyName(keyName)) {
      desc = m.descs[keyName];
      if (desc && desc.didUnwatch) { desc.didUnwatch(obj, keyName); }

      if ('function' === typeof obj.didUnwatchProperty) {
        obj.didUnwatchProperty(keyName);
      }

      if (MANDATORY_SETTER && keyName in obj) {
        o_defineProperty(obj, keyName, {
          configurable: true,
          enumerable: true,
          writable: true,
          value: m.values[keyName]
        });
        delete m.values[keyName];
      }
    } else {
      chainsFor(obj).remove(keyName);
    }

  } else if (watching[keyName]>1) {
    watching[keyName]--;
  }

  return this;
};

/**
  @private

  Call on an object when you first beget it from another object. This will
  setup any chained watchers on the object instance as needed. This method is
  safe to call multiple times.

  @method rewatch
  @for Ember
  @param obj
*/
Ember.rewatch = function(obj) {
  var m = metaFor(obj, false), chains = m.chains;

  // make sure the object has its own guid.
  if (GUID_KEY in obj && !obj.hasOwnProperty(GUID_KEY)) {
    Ember.generateGuid(obj, 'ember');
  }

  // make sure any chained watchers update.
  if (chains && chains.value() !== obj) {
    m.chains = chains.copy(obj);
  }

  return this;
};

Ember.finishChains = function(obj) {
  var m = metaFor(obj, false), chains = m.chains;
  if (chains) {
    if (chains.value() !== obj) {
      m.chains = chains = chains.copy(obj);
    }
    chains.didChange(true);
  }
};

// ..........................................................
// PROPERTY CHANGES
//

/**
  This function is called just before an object property is about to change.
  It will notify any before observers and prepare caches among other things.

  Normally you will not need to call this method directly but if for some
  reason you can't directly watch a property you can invoke this method
  manually along with `Ember.propertyDidChange()` which you should call just
  after the property value changes.

  @method propertyWillChange
  @for Ember
  @param {Object} obj The object with the property that will change
  @param {String} keyName The property key (or path) that will change.
  @return {void}
*/
function propertyWillChange(obj, keyName, value) {
  var m = metaFor(obj, false),
      watching = m.watching[keyName] > 0 || keyName === 'length',
      proto = m.proto,
      desc = m.descs[keyName];

  if (!watching) { return; }
  if (proto === obj) { return; }
  if (desc && desc.willChange) { desc.willChange(obj, keyName); }
  dependentKeysWillChange(obj, keyName, m);
  chainsWillChange(obj, keyName, m);
  Ember.notifyBeforeObservers(obj, keyName);
}

Ember.propertyWillChange = propertyWillChange;

/**
  This function is called just after an object property has changed.
  It will notify any observers and clear caches among other things.

  Normally you will not need to call this method directly but if for some
  reason you can't directly watch a property you can invoke this method
  manually along with `Ember.propertyWilLChange()` which you should call just
  before the property value changes.

  @method propertyDidChange
  @for Ember
  @param {Object} obj The object with the property that will change
  @param {String} keyName The property key (or path) that will change.
  @return {void}
*/
function propertyDidChange(obj, keyName) {
  var m = metaFor(obj, false),
      watching = m.watching[keyName] > 0 || keyName === 'length',
      proto = m.proto,
      desc = m.descs[keyName];

  if (proto === obj) { return; }

  // shouldn't this mean that we're watching this key?
  if (desc && desc.didChange) { desc.didChange(obj, keyName); }
  if (!watching && keyName !== 'length') { return; }

  dependentKeysDidChange(obj, keyName, m);
  chainsDidChange(obj, keyName, m);
  Ember.notifyObservers(obj, keyName);
}

Ember.propertyDidChange = propertyDidChange;

var NODE_STACK = [];

/**
  Tears down the meta on an object so that it can be garbage collected.
  Multiple calls will have no effect.

  @method destroy
  @for Ember
  @param {Object} obj  the object to destroy
  @return {void}
*/
Ember.destroy = function (obj) {
  var meta = obj[META_KEY], node, nodes, key, nodeObject;
  if (meta) {
    obj[META_KEY] = null;
    // remove chainWatchers to remove circular references that would prevent GC
    node = meta.chains;
    if (node) {
      NODE_STACK.push(node);
      // process tree
      while (NODE_STACK.length > 0) {
        node = NODE_STACK.pop();
        // push children
        nodes = node._chains;
        if (nodes) {
          for (key in nodes) {
            if (nodes.hasOwnProperty(key)) {
              NODE_STACK.push(nodes[key]);
            }
          }
        }
        // remove chainWatcher in node object
        if (node._watching) {
          nodeObject = node._object;
          if (nodeObject) {
            removeChainWatcher(nodeObject, node._key, node);
          }
        }
      }
    }
  }
};

})();



(function() {
/**
@module ember-metal
*/

Ember.warn("The CP_DEFAULT_CACHEABLE flag has been removed and computed properties are always cached by default. Use `volatile` if you don't want caching.", Ember.ENV.CP_DEFAULT_CACHEABLE !== false);


var get = Ember.get,
    set = Ember.set,
    metaFor = Ember.meta,
    guidFor = Ember.guidFor,
    a_slice = [].slice,
    o_create = Ember.create,
    META_KEY = Ember.META_KEY,
    watch = Ember.watch,
    unwatch = Ember.unwatch;

// ..........................................................
// DEPENDENT KEYS
//

// data structure:
//  meta.deps = {
//   'depKey': {
//     'keyName': count,
//   }
//  }

/*
  This function returns a map of unique dependencies for a
  given object and key.
*/
function keysForDep(obj, depsMeta, depKey) {
  var keys = depsMeta[depKey];
  if (!keys) {
    // if there are no dependencies yet for a the given key
    // create a new empty list of dependencies for the key
    keys = depsMeta[depKey] = {};
  } else if (!depsMeta.hasOwnProperty(depKey)) {
    // otherwise if the dependency list is inherited from
    // a superclass, clone the hash
    keys = depsMeta[depKey] = o_create(keys);
  }
  return keys;
}

/* return obj[META_KEY].deps */
function metaForDeps(obj, meta) {
  var deps = meta.deps;
  // If the current object has no dependencies...
  if (!deps) {
    // initialize the dependencies with a pointer back to
    // the current object
    deps = meta.deps = {};
  } else if (!meta.hasOwnProperty('deps')) {
    // otherwise if the dependencies are inherited from the
    // object's superclass, clone the deps
    deps = meta.deps = o_create(deps);
  }
  return deps;
}

function addDependentKeys(desc, obj, keyName, meta) {
  // the descriptor has a list of dependent keys, so
  // add all of its dependent keys.
  var depKeys = desc._dependentKeys, depsMeta, idx, len, depKey, keys;
  if (!depKeys) return;

  depsMeta = metaForDeps(obj, meta);

  for(idx = 0, len = depKeys.length; idx < len; idx++) {
    depKey = depKeys[idx];
    // Lookup keys meta for depKey
    keys = keysForDep(obj, depsMeta, depKey);
    // Increment the number of times depKey depends on keyName.
    keys[keyName] = (keys[keyName] || 0) + 1;
    // Watch the depKey
    watch(obj, depKey);
  }
}

function removeDependentKeys(desc, obj, keyName, meta) {
  // the descriptor has a list of dependent keys, so
  // add all of its dependent keys.
  var depKeys = desc._dependentKeys, depsMeta, idx, len, depKey, keys;
  if (!depKeys) return;

  depsMeta = metaForDeps(obj, meta);

  for(idx = 0, len = depKeys.length; idx < len; idx++) {
    depKey = depKeys[idx];
    // Lookup keys meta for depKey
    keys = keysForDep(obj, depsMeta, depKey);
    // Increment the number of times depKey depends on keyName.
    keys[keyName] = (keys[keyName] || 0) - 1;
    // Watch the depKey
    unwatch(obj, depKey);
  }
}

// ..........................................................
// COMPUTED PROPERTY
//

/**
  @class ComputedProperty
  @namespace Ember
  @extends Ember.Descriptor
  @constructor
*/
function ComputedProperty(func, opts) {
  this.func = func;
  this._cacheable = (opts && opts.cacheable !== undefined) ? opts.cacheable : true;
  this._dependentKeys = opts && opts.dependentKeys;
}

Ember.ComputedProperty = ComputedProperty;
ComputedProperty.prototype = new Ember.Descriptor();

var ComputedPropertyPrototype = ComputedProperty.prototype;

/**
  Call on a computed property to set it into cacheable mode. When in this
  mode the computed property will automatically cache the return value of
  your function until one of the dependent keys changes.

  ```javascript
  MyApp.president = Ember.Object.create({
    fullName: function() {
      return this.get('firstName') + ' ' + this.get('lastName');

      // After calculating the value of this function, Ember will
      // return that value without re-executing this function until
      // one of the dependent properties change.
    }.property('firstName', 'lastName')
  });
  ```

  Properties are cacheable by default.

  @method cacheable
  @param {Boolean} aFlag optional set to `false` to disable caching
  @chainable
*/
ComputedPropertyPrototype.cacheable = function(aFlag) {
  this._cacheable = aFlag !== false;
  return this;
};

/**
  Call on a computed property to set it into non-cached mode. When in this
  mode the computed property will not automatically cache the return value.

  ```javascript
  MyApp.outsideService = Ember.Object.create({
    value: function() {
      return OutsideService.getValue();
    }.property().volatile()
  });
  ```

  @method volatile
  @chainable
*/
ComputedPropertyPrototype.volatile = function() {
  return this.cacheable(false);
};

/**
  Sets the dependent keys on this computed property. Pass any number of
  arguments containing key paths that this computed property depends on.

  ```javascript
  MyApp.president = Ember.Object.create({
    fullName: Ember.computed(function() {
      return this.get('firstName') + ' ' + this.get('lastName');

      // Tell Ember that this computed property depends on firstName
      // and lastName
    }).property('firstName', 'lastName')
  });
  ```

  @method property
  @param {String} path* zero or more property paths
  @chainable
*/
ComputedPropertyPrototype.property = function() {
  var args = [];
  for (var i = 0, l = arguments.length; i < l; i++) {
    args.push(arguments[i]);
  }
  this._dependentKeys = args;
  return this;
};

/**
  In some cases, you may want to annotate computed properties with additional
  metadata about how they function or what values they operate on. For example,
  computed property functions may close over variables that are then no longer
  available for introspection.

  You can pass a hash of these values to a computed property like this:

  ```
  person: function() {
    var personId = this.get('personId');
    return App.Person.create({ id: personId });
  }.property().meta({ type: App.Person })
  ```

  The hash that you pass to the `meta()` function will be saved on the
  computed property descriptor under the `_meta` key. Ember runtime
  exposes a public API for retrieving these values from classes,
  via the `metaForProperty()` function.

  @method meta
  @param {Hash} meta
  @chainable
*/

ComputedPropertyPrototype.meta = function(meta) {
  if (arguments.length === 0) {
    return this._meta || {};
  } else {
    this._meta = meta;
    return this;
  }
};

/* impl descriptor API */
ComputedPropertyPrototype.willWatch = function(obj, keyName) {
  // watch already creates meta for this instance
  var meta = obj[META_KEY];
  Ember.assert('watch should have setup meta to be writable', meta.source === obj);
  if (!(keyName in meta.cache)) {
    addDependentKeys(this, obj, keyName, meta);
  }
};

ComputedPropertyPrototype.didUnwatch = function(obj, keyName) {
  var meta = obj[META_KEY];
  Ember.assert('unwatch should have setup meta to be writable', meta.source === obj);
  if (!(keyName in meta.cache)) {
    // unwatch already creates meta for this instance
    removeDependentKeys(this, obj, keyName, meta);
  }
};

/* impl descriptor API */
ComputedPropertyPrototype.didChange = function(obj, keyName) {
  // _suspended is set via a CP.set to ensure we don't clear
  // the cached value set by the setter
  if (this._cacheable && this._suspended !== obj) {
    var meta = metaFor(obj);
    if (keyName in meta.cache) {
      delete meta.cache[keyName];
      if (!meta.watching[keyName]) {
        removeDependentKeys(this, obj, keyName, meta);
      }