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Class Ember.MutableEnumerable public


Uses: Ember.Enumerable
Defined in: packages/ember-runtime/lib/mixins/mutable_enumerable.js:11
Module: ember

This mixin defines the API for modifying generic enumerables. These methods can be applied to an object regardless of whether it is ordered or unordered.

Note that an Enumerable can change even if it does not implement this mixin. For example, a MappedEnumerable cannot be directly modified but if its underlying enumerable changes, it will change also.

Adding Objects

To add an object to an enumerable, use the addObject() method. This method will only add the object to the enumerable if the object is not already present and is of a type supported by the enumerable.

set.addObject(contact);

Removing Objects

To remove an object from an enumerable, use the removeObject() method. This will only remove the object if it is present in the enumerable, otherwise this method has no effect.

set.removeObject(contact);

Implementing In Your Own Code

If you are implementing an object and want to support this API, just include this mixin in your class and implement the required methods. In your unit tests, be sure to apply the Ember.MutableEnumerableTests to your object.


Methods

addObject (object) : Object public

Module: ember

Defined in packages/ember-runtime/lib/mixins/mutable_enumerable.js:53

object
Object

The object to add to the enumerable.

returns
Object

the passed object

Required. You must implement this method to apply this mixin.

Attempts to add the passed object to the receiver if the object is not already present in the collection. If the object is present, this method has no effect.

If the passed object is of a type not supported by the receiver, then this method should raise an exception.

addObjects (objects) : Object public

Module: ember

Defined in packages/ember-runtime/lib/mixins/mutable_enumerable.js:70

objects
Ember.Enumerable

the objects to add.

returns
Object

receiver

Adds each object in the passed enumerable to the receiver.

compact : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:914

returns
Array

the array without null and undefined elements.

Returns a copy of the array with all null and undefined elements removed.

var arr = ['a', null, 'c', undefined];
arr.compact();  // ['a', 'c']

contains (obj) : Boolean public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:213

obj
Object

The object to search for.

returns
Boolean

true if object is found in enumerable.

Returns true if the passed object can be found in the receiver. The default version will iterate through the enumerable until the object is found. You may want to override this with a more efficient version.

var arr = ['a', 'b', 'c'];

arr.contains('a'); // true
arr.contains('z'); // false

every (callback, target) : Boolean public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:613

callback
Function

The callback to execute

target
Object

The target object to use

returns
Boolean

Returns true if the passed function returns true for every item in the enumeration. This corresponds with the every() method in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • enumerable is the enumerable object itself.

It should return the true or false.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

Example Usage:

if (people.every(isEngineer)) {
  Paychecks.addBigBonus();
}

filter (callback, target) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:381

callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

A filtered array.

Returns an array with all of the items in the enumeration that the passed function returns true for. This method corresponds to filter() defined in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • enumerable is the enumerable object itself.

It should return true to include the item in the results, false otherwise.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

filterBy (key, value) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:455

key
String

the property to test

value
*

optional value to test against.

returns
Array

filtered array

Returns an array with just the items with the matched property. You can pass an optional second argument with the target value. Otherwise this will match any property that evaluates to true.

find (callback, target) : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:523

callback
Function

The callback to execute

target
Object

The target object to use

returns
Object

Found item or undefined.

Returns the first item in the array for which the callback returns true. This method works similar to the filter() method defined in JavaScript 1.6 except that it will stop working on the array once a match is found.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • enumerable is the enumerable object itself.

It should return the true to include the item in the results, false otherwise.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

findBy (key, value) : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:580

key
String

the property to test

value
String

optional value to test against.

returns
Object

found item or undefined

Returns the first item with a property matching the passed value. You can pass an optional second argument with the target value. Otherwise this will match any property that evaluates to true.

This method works much like the more generic find() method.

forEach (callback, target) : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:238

callback
Function

The callback to execute

target
Object

The target object to use

returns
Object

receiver

Iterates through the enumerable, calling the passed function on each item. This method corresponds to the forEach() method defined in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • enumerable is the enumerable object itself.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

getEach (key) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:289

key
String

name of the property

returns
Array

The mapped array.

Alias for mapBy

isEvery (key, value) : Boolean public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:674

Available since v1.3.0

key
String

the property to test

value
String

optional value to test against. Defaults to true

returns
Boolean

Returns true if the passed property resolves to the value of the second argument for all items in the enumerable. This method is often simpler/faster than using a callback.

map (callback, target) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:317

callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

The mapped array.

Maps all of the items in the enumeration to another value, returning a new array. This method corresponds to map() defined in JavaScript 1.6.

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • enumerable is the enumerable object itself.

It should return the mapped value.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. This is a good way to give your iterator function access to the current object.

mapBy (key) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:354

key
String

name of the property

returns
Array

The mapped array.

Similar to map, this specialized function returns the value of the named property on all items in the enumeration.

reject (callback, target) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:422

callback
Function

The callback to execute

target
Object

The target object to use

returns
Array

A rejected array.

Returns an array with all of the items in the enumeration where the passed function returns false. This method is the inverse of filter().

The callback method you provide should have the following signature (all parameters are optional):

function(item, index, enumerable);
  • item is the current item in the iteration.
  • index is the current index in the iteration
  • enumerable is the enumerable object itself.

It should return a falsey value to include the item in the results.

Note that in addition to a callback, you can also pass an optional target object that will be set as "this" on the context. This is a good way to give your iterator function access to the current object.

rejectBy (key, value) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:484

key
String

the property to test

value
String

optional value to test against.

returns
Array

rejected array

Returns an array with the items that do not have truthy values for key. You can pass an optional second argument with the target value. Otherwise this will match any property that evaluates to false.

removeObject (object) : Object public

Module: ember

Defined in packages/ember-runtime/lib/mixins/mutable_enumerable.js:85

object
Object

The object to remove from the enumerable.

returns
Object

the passed object

Required. You must implement this method to apply this mixin.

Attempts to remove the passed object from the receiver collection if the object is present in the collection. If the object is not present, this method has no effect.

If the passed object is of a type not supported by the receiver, then this method should raise an exception.

removeObjects (objects) : Object public

Module: ember

Defined in packages/ember-runtime/lib/mixins/mutable_enumerable.js:103

objects
Ember.Enumerable

the objects to remove

returns
Object

receiver

Removes each object in the passed enumerable from the receiver.

setEach (key, value) : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:299

key
String

The key to set

value
Object

The object to set

returns
Object

receiver

Sets the value on the named property for each member. This is more efficient than using other methods defined on this helper. If the object implements Ember.Observable, the value will be changed to set(), otherwise it will be set directly. null objects are skipped.

sortBy (property) : Array public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:1189

Available since v1.2.0

property
String

name(s) to sort on

returns
Array

The sorted array.

Converts the enumerable into an array and sorts by the keys specified in the argument.

You may provide multiple arguments to sort by multiple properties.

without (value) : Ember.Enumerable public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:932

value
Object
returns
Ember.Enumerable

Returns a new enumerable that excludes the passed value. The default implementation returns an array regardless of the receiver type unless the receiver does not contain the value.

var arr = ['a', 'b', 'a', 'c'];
arr.without('a');  // ['b', 'c']

Properties

firstObject : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:138

returns
Object

the object or undefined

Helper method returns the first object from a collection. This is usually used by bindings and other parts of the framework to extract a single object if the enumerable contains only one item.

If you override this method, you should implement it so that it will always return the same value each time it is called. If your enumerable contains only one object, this method should always return that object. If your enumerable is empty, this method should return undefined.

var arr = ['a', 'b', 'c'];
arr.get('firstObject');  // 'a'

var arr = [];
arr.get('firstObject');  // undefined

lastObject : Object public

Module: ember

Inherited from Ember.Enumerable packages/ember-runtime/lib/mixins/enumerable.js:174

returns
Object

the last object or undefined

Helper method returns the last object from a collection. If your enumerable contains only one object, this method should always return that object. If your enumerable is empty, this method should return undefined.

var arr = ['a', 'b', 'c'];
arr.get('lastObject');  // 'c'

var arr = [];
arr.get('lastObject');  // undefined
On this page


Methods

  • addObject
  • addObjects
  • compact
  • contains
  • every
  • filter
  • filterBy
  • find
  • findBy
  • forEach
  • getEach
  • isEvery
  • map
  • mapBy
  • reject
  • rejectBy
  • removeObject
  • removeObjects
  • setEach
  • sortBy
  • without

Properties

  • firstObject
  • lastObject
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