Class MutableArray

public

This mixin defines the API for modifying array-like objects. These methods can be applied only to a collection that keeps its items in an ordered set. It builds upon the Array mixin and adds methods to modify the array. One concrete implementations of this class include ArrayProxy.

It is important to use the methods in this class to modify arrays so that changes are observable. This allows the binding system in Ember to function correctly.

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

Show:

Module: @ember/array
target
Object
The observer object.
opts
Object
Optional hash of configuration options including `willChange` and `didChange` option.
returns
EmberArray
receiver

Adds an array observer to the receiving array. The array observer object normally must implement two methods:

  • willChange(observedObj, start, removeCount, addCount) - This method will be called just before the array is modified.
  • didChange(observedObj, start, removeCount, addCount) - This method will be called just after the array is modified.

Both callbacks will be passed the observed object, starting index of the change as well as a count of the items to be removed and added. You can use these callbacks to optionally inspect the array during the change, clear caches, or do any other bookkeeping necessary.

In addition to passing a target, you can also include an options hash which you can use to override the method names that will be invoked on the target.

Module: @ember/array
obj
*
object to add, if not already present
returns
EmberArray
receiver

Push the object onto the end of the array if it is not already present in the array.

1
2
3
4
let cities = ['Chicago', 'Berlin'];

cities.addObject('Lima');    // ['Chicago', 'Berlin', 'Lima']
cities.addObject('Berlin');  // ['Chicago', 'Berlin', 'Lima']
Module: @ember/array
objects
EmberArray
the objects to add.
returns
EmberArray
receiver

Adds each object in the passed array to the receiver.

Module: @ember/array
callback
Function
The callback to execute
target
Object
The target object to use
returns
Boolean
`true` if the passed function returns `true` for any item

Returns true if the passed function returns true for any item in the enumeration.

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

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array object itself.

It must return a truthy value (i.e. true) to include an item in the results. Any non-truthy return value will discard the item from 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.

Usage Example:

1
2
3
if (people.any(isManager)) {
  Paychecks.addBiggerBonus();
}
Module: @ember/array
startIdx
Number
The starting index in the array that did change.
removeAmt
Number
The number of items that were removed. If you pass `null` assumes 0
addAmt
Number
The number of items that were added. If you pass `null` assumes 0.
returns
EmberArray
receiver

If you are implementing an object that supports EmberArray, call this method just after the array content changes to notify any observers and invalidate any related properties. Pass the starting index of the change as well as a delta of the amounts to change.

Module: @ember/array
startIdx
Number
The starting index in the array that will change.
removeAmt
Number
The number of items that will be removed. If you pass `null` assumes 0
addAmt
Number
The number of items that will be added. If you pass `null` assumes 0.
returns
EmberArray
receiver

If you are implementing an object that supports EmberArray, call this method just before the array content changes to notify any observers and invalidate any related properties. Pass the starting index of the change as well as a delta of the amounts to change.

Module: @ember/array
returns
Array
An empty Array.

Remove all elements from the array. This is useful if you want to reuse an existing array without having to recreate it.

1
2
3
4
5
let colors = ['red', 'green', 'blue'];

colors.length;  // 3
colors.clear(); // []
colors.length;  // 0
Module: @ember/array
returns
Array
the array without null and undefined elements.

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

1
2
let arr = ['a', null, 'c', undefined];
arr.compact();  // ['a', 'c']
Module: @ember/array
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):

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array 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:

1
2
3
if (people.every(isEngineer)) {
  Paychecks.addBigBonus();
}
Module: @ember/array
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):

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array 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.

Module: @ember/array
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.

Example Usage:

1
2
const things = Ember.A().addObjects([{food: 'apple'}, {food: 'beans'}]);
things.filterBy('food', 'beans'); // [{food: 'beans'}]
Module: @ember/array
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 is similar to the find() method defined in ECMAScript 2015.

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

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array 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.

Module: @ember/array
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.

Module: @ember/array
callback
Function
The callback to execute
target
Object
The target object to use
returns
Object
receiver

Iterates through the array, 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):

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array 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.

Module: @ember/array
key
String
name of the property
returns
Array
The mapped array.

Alias for mapBy

Module: @ember/array
object
Object
The object to search for.
startAt
Number
optional starting location to search, default 0
returns
Boolean
`true` if object is found in the array.

Returns true if the passed object can be found in the array. This method is a Polyfill for ES 2016 Array.includes. If no startAt argument is given, the starting location to search is 0. If it's negative, searches from the index of this.length + startAt by asc.

1
2
3
4
5
6
7
8
[1, 2, 3].includes(2);     // true
[1, 2, 3].includes(4);     // false
[1, 2, 3].includes(3, 2);  // true
[1, 2, 3].includes(3, 3);  // false
[1, 2, 3].includes(3, -1); // true
[1, 2, 3].includes(1, -1); // false
[1, 2, 3].includes(1, -4); // true
[1, 2, NaN].includes(NaN); // true
Module: @ember/array
object
Object
the item to search for
startAt
Number
optional starting location to search, default 0
returns
Number
index or -1 if not found

Returns the index of the given object's first occurrence. If no startAt argument is given, the starting location to search is 0. If it's negative, will count backward from the end of the array. Returns -1 if no match is found.

1
2
3
4
5
6
7
8
let arr = ['a', 'b', 'c', 'd', 'a'];

arr.indexOf('a');       //  0
arr.indexOf('z');       // -1
arr.indexOf('a', 2);    //  4
arr.indexOf('a', -1);   //  4
arr.indexOf('b', 3);    // -1
arr.indexOf('a', 100);  // -1
Module: @ember/array
idx
Number
index of insert the object at.
object
Object
object to insert
returns
EmberArray
receiver

This will use the primitive replace() method to insert an object at the specified index.

1
2
3
4
let colors = ['red', 'green', 'blue'];

colors.insertAt(2, 'yellow');  // ['red', 'green', 'yellow', 'blue']
colors.insertAt(5, 'orange');  // Error: Index out of range
Module: @ember/array
methodName
String
the name of the method
args
Object...
optional arguments to pass as well.
returns
Array
return values from calling invoke.

Invokes the named method on every object in the receiver that implements it. This method corresponds to the implementation in Prototype 1.6.

Module: @ember/array

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 any item in the array. This method is often simpler/faster than using a callback.

Module: @ember/array

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 array. This method is often simpler/faster than using a callback.

Note that like the native Array.every, isEvery will return true when called on any empty array.

Module: @ember/array
object
Object
the item to search for
startAt
Number
optional starting location to search, default 0
returns
Number
index or -1 if not found

Returns the index of the given object's last occurrence. If no startAt argument is given, the search starts from the last position. If it's negative, will count backward from the end of the array. Returns -1 if no match is found.

1
2
3
4
5
6
7
8
let arr = ['a', 'b', 'c', 'd', 'a'];

arr.lastIndexOf('a');       //  4
arr.lastIndexOf('z');       // -1
arr.lastIndexOf('a', 2);    //  0
arr.lastIndexOf('a', -1);   //  4
arr.lastIndexOf('b', 3);    //  1
arr.lastIndexOf('a', 100);  //  4
Module: @ember/array
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):

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array 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.

Module: @ember/array
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.

Module: @ember/array
idx
Number
The index of the item to return.
returns
*
item at index or undefined

Returns the object at the given index. If the given index is negative or is greater or equal than the array length, returns undefined.

This is one of the primitives you must implement to support EmberArray. If your object supports retrieving the value of an array item using get() (i.e. myArray.get(0)), then you do not need to implement this method yourself.

1
2
3
4
5
6
7
let arr = ['a', 'b', 'c', 'd'];

arr.objectAt(0);   // 'a'
arr.objectAt(3);   // 'd'
arr.objectAt(-1);  // undefined
arr.objectAt(4);   // undefined
arr.objectAt(5);   // undefined
Module: @ember/array
indexes
Array
An array of indexes of items to return.
returns
Array

This returns the objects at the specified indexes, using objectAt.

1
2
3
4
let arr = ['a', 'b', 'c', 'd'];

arr.objectsAt([0, 1, 2]);  // ['a', 'b', 'c']
arr.objectsAt([2, 3, 4]);  // ['c', 'd', undefined]
Module: @ember/array
returns
object

Pop object from array or nil if none are left. Works just like pop() but it is KVO-compliant.

1
2
3
4
let colors = ['red', 'green', 'blue'];

colors.popObject();   // 'blue'
console.log(colors);  // ['red', 'green']
Module: @ember/array
obj
*
object to push
returns
object same object passed as a param

Push the object onto the end of the array. Works just like push() but it is KVO-compliant.

1
2
3
4
let colors = ['red', 'green'];

colors.pushObject('black');     // ['red', 'green', 'black']
colors.pushObject(['yellow']);  // ['red', 'green', ['yellow']]
Module: @ember/array
objects
EmberArray
the objects to add
returns
EmberArray
receiver

Add the objects in the passed array to the end of the array. Defers notifying observers of the change until all objects are added.

1
2
3
let colors = ['red'];

colors.pushObjects(['yellow', 'orange']);  // ['red', 'yellow', 'orange']
Module: @ember/array
callback
Function
The callback to execute
initialValue
Object
Initial value for the reduce
returns
Object
The reduced value.

This will combine the values of the enumerator into a single value. It is a useful way to collect a summary value from an enumeration. This corresponds to the reduce() method defined in JavaScript 1.8.

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

1
function(previousValue, item, index, array);
  • previousValue is the value returned by the last call to the iterator.
  • item is the current item in the iteration.
  • index is the current index in the iteration.
  • array is the array itself.

Return the new cumulative value.

In addition to the callback you can also pass an initialValue. An error will be raised if you do not pass an initial value and the enumerator is empty.

Note that unlike the other methods, this method does not allow you to pass a target object to set as this for the callback. It's part of the spec. Sorry.

Module: @ember/array
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):

1
function(item, index, array);
  • item is the current item in the iteration.
  • index is the current index in the iteration
  • array is the array 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.

Module: @ember/array
key
String
the property to test
value
*
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.

Module: @ember/array
target
Object
The object observing the array.
opts
Object
Optional hash of configuration options including `willChange` and `didChange` option.
returns
EmberArray
receiver

Removes an array observer from the object if the observer is current registered. Calling this method multiple times with the same object will have no effect.

Module: @ember/array
start
Number
index, start of range
len
Number
length of passing range
returns
EmberArray
receiver

Remove an object at the specified index using the replace() primitive method. You can pass either a single index, or a start and a length.

If you pass a start and length that is beyond the length this method will throw an assertion.

1
2
3
4
5
let colors = ['red', 'green', 'blue', 'yellow', 'orange'];

colors.removeAt(0);     // ['green', 'blue', 'yellow', 'orange']
colors.removeAt(2, 2);  // ['green', 'blue']
colors.removeAt(4, 2);  // Error: Index out of range
Module: @ember/array
obj
*
object to remove
returns
EmberArray
receiver

Remove all occurrences of an object in the array.

1
2
3
4
5
let cities = ['Chicago', 'Berlin', 'Lima', 'Chicago'];

cities.removeObject('Chicago');  // ['Berlin', 'Lima']
cities.removeObject('Lima');     // ['Berlin']
cities.removeObject('Tokyo')     // ['Berlin']
Module: @ember/array
objects
EmberArray
the objects to remove
returns
EmberArray
receiver

Removes each object in the passed array from the receiver.

Module: @ember/array
idx
Number
Starting index in the array to replace. If idx >= length, then append to the end of the array.
amt
Number
Number of elements that should be removed from the array, starting at *idx*.
objects
EmberArray
An array of zero or more objects that should be inserted into the array at *idx*

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

This is one of the primitives you must implement to support Array. You should replace amt objects started at idx with the objects in the passed array. You should also call this.arrayContentDidChange()

Note that this method is expected to validate the type(s) of objects that it expects.

Module: @ember/array
returns
EmberArray
receiver

Reverse objects in the array. Works just like reverse() but it is KVO-compliant.

Module: @ember/array
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 ergonomic than using other methods defined on this helper. If the object implements Observable, the value will be changed to set(), otherwise it will be set directly. null objects are skipped.

Module: @ember/array
objects
EmberArray
array whose content will be used for replacing the content of the receiver
returns
EmberArray
receiver with the new content

Replace all the receiver's content with content of the argument. If argument is an empty array receiver will be cleared.

1
2
3
4
let colors = ['red', 'green', 'blue'];

colors.setObjects(['black', 'white']);  // ['black', 'white']
colors.setObjects([]);                  // []
Module: @ember/array
returns
object

Shift an object from start of array or nil if none are left. Works just like shift() but it is KVO-compliant.

1
2
3
4
let colors = ['red', 'green', 'blue'];

colors.shiftObject();  // 'red'
console.log(colors);   // ['green', 'blue']
Module: @ember/array
beginIndex
Number
(Optional) index to begin slicing from.
endIndex
Number
(Optional) index to end the slice at (but not included).
returns
Array
New array with specified slice

Returns a new array that is a slice of the receiver. This implementation uses the observable array methods to retrieve the objects for the new slice.

1
2
3
4
5
let arr = ['red', 'green', 'blue'];

arr.slice(0);       // ['red', 'green', 'blue']
arr.slice(0, 2);    // ['red', 'green']
arr.slice(1, 100);  // ['green', 'blue']
Module: @ember/array

Available since v1.2.0

property
String
name(s) to sort on
returns
Array
The sorted array.

Sorts the array by the keys specified in the argument.

You may provide multiple arguments to sort by multiple properties.

1
2
   let colors = [{name: 'red'}, {name: 'green'}, {name: 'blue'}];
   colors.sortBy('name'); // [{name: 'blue'}, {name: 'green'}, {name: 'red'}]
Module: @ember/array
returns
Array
the object as an array.

Simply converts the object into a genuine array. The order is not guaranteed. Corresponds to the method implemented by Prototype.

Module: @ember/array
returns
EmberArray

Returns a new array that contains only unique values. The default implementation returns an array regardless of the receiver type.

1
2
let arr = ['a', 'a', 'b', 'b'];
arr.uniq();  // ['a', 'b']

This only works on primitive data types, e.g. Strings, Numbers, etc.

Module: @ember/array
key
String,Function
returns
EmberArray

Returns a new array that contains only items containing a unique property value. The default implementation returns an array regardless of the receiver type.

1
2
3
4
5
let arr = [{ value: 'a' }, { value: 'a' }, { value: 'b' }, { value: 'b' }];
arr.uniqBy('value');  // [{ value: 'a' }, { value: 'b' }]

let arr = [2.2, 2.1, 3.2, 3.3];
arr.uniqBy(Math.floor);  // [2.2, 3.2];
Module: @ember/array
obj
*
object to unshift
returns
object same object passed as a param

Unshift an object to start of array. Works just like unshift() but it is KVO-compliant.

1
2
3
4
let colors = ['red'];

colors.unshiftObject('yellow');    // ['yellow', 'red']
colors.unshiftObject(['black']);   // [['black'], 'yellow', 'red']
Module: @ember/array
objects
Enumberable
the objects to add
returns
EmberArray
receiver

Adds the named objects to the beginning of the array. Defers notifying observers until all objects have been added.

1
2
3
4
let colors = ['red'];

colors.unshiftObjects(['black', 'white']);   // ['black', 'white', 'red']
colors.unshiftObjects('yellow'); // Type Error: 'undefined' is not a function
Module: @ember/array
value
Object
returns
EmberArray

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

1
2
let arr = ['a', 'b', 'a', 'c'];
arr.without('a');  // ['b', 'c']