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Ember.Map Class

PRIVATE

Defined in: packages/ember-metal/lib/map.js:221

Module: ember-metal

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.

clearprivate

Defined in packages/ember-metal/lib/map.js:391

copyEmber.Mapprivate

Defined in packages/ember-metal/lib/map.js:401

Returns:

Ember.Map

createprivatestatic

Defined in packages/ember-metal/lib/map.js:252

delete (key) Booleanprivate

Defined in packages/ember-metal/lib/map.js:320
Available since 1.8.0

Removes a value from the map for an associated key.

Parameters:

key *

Returns:

Boolean
true if an item was removed, false otherwise

forEach (callback, self) private

Defined in packages/ember-metal/lib/map.js:358

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

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

Parameters:

callback Function
self *
if passed, the `this` value inside the callback. By default, `this` is the map.

get (key) *private

Defined in packages/ember-metal/lib/map.js:276

Retrieve the value associated with a given key.

Parameters:

key *

Returns:

*
the value associated with the key, or `undefined`

has (key) Booleanprivate

Defined in packages/ember-metal/lib/map.js:346

Check whether a key is present.

Parameters:

key *

Returns:

Boolean
true if the item was present, false otherwise

set (key, value) Ember.Mapprivate

Defined in packages/ember-metal/lib/map.js:293

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.

Parameters:

key *
value *

Returns:

Ember.Map

sizenumberprivate

Defined in packages/ember-metal/lib/map.js:265
Available since 1.8.0

This property will change as the number of objects in the map changes.

Default: 0

© 2017 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
http://emberjs.com/api/classes/Ember.Map.html