Class Enumerable

private
Defined in: packages/ember-runtime/lib/mixins/enumerable.js:56
Module: @ember/enumerable
Since: vEmber 0.9

any (callback, target) Boolean public

Module: @ember/enumerable
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):

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 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:

if (people.any(isManager)) {
  Paychecks.addBiggerBonus();
}

compact Array public

Module: @ember/enumerable
returns
Array
the array without null and undefined elements.

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

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

every (callback, target) Boolean public

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

Alias for mapBy

includes (obj) Boolean public

Module: @ember/enumerable
obj
Object
The object to search for.
returns
Boolean
`true` if object is found in the enumerable.

Returns true if the passed object can be found in the enumerable.

[1, 2, 3].includes(2);                     // true
[1, 2, 3].includes(4);                     // false
[1, 2, undefined].includes(undefined);     // true
[1, 2, null].includes(null);               // true
[1, 2, NaN].includes(NaN);                 // true

invoke (methodName, args) Array public

Module: @ember/enumerable
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.

isAny (key, value) Boolean public

Module: @ember/enumerable

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

isEvery (key, value) Boolean public

Module: @ember/enumerable

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.

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

map (callback, target) Array public

Module: @ember/enumerable
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/enumerable
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.

reduce (callback, initialValue, reducerProperty) Object public

Module: @ember/enumerable
callback
Function
The callback to execute
initialValue
Object
Initial value for the reduce
reducerProperty
String
internal use only.
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):

function(previousValue, item, index, enumerable);
  • 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.
  • enumerable is the enumerable object 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.

reject (callback, target) Array public

Module: @ember/enumerable
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/enumerable
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.

setEach (key, value) Object public

Module: @ember/enumerable
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 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/enumerable

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.

toArray Array public

Module: @ember/enumerable
returns
Array
the enumerable as an array.

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

uniq Ember.Enumerable public

Module: @ember/enumerable
returns
Ember.Enumerable

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

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

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

uniqBy Ember.Enumerable public

Module: @ember/enumerable
returns
Ember.Enumerable

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

let arr = [{ value: 'a' }, { value: 'a' }, { value: 'b' }, { value: 'b' }];
arr.uniqBy('value');  // [{ value: 'a' }, { value: 'b' }]

without (value) Ember.Enumerable public

Module: @ember/enumerable
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. If the receiver does not contain the value it returns the original enumerable.

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

© 2020 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://api.emberjs.com/ember/2.18/classes/Enumerable/methods