Class EmberArray

addArrayObserver (target, opts) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:483

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.

any (callback, target) Boolean public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1179

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

The any() method executes the callback function once for each element present in the array until it finds the one where callback returns a truthy value (i.e. true). If such an element is found, any() immediately returns true. Otherwise, any() returns false.

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.

Note that in addition to a callback, you can also pass an optional target object that will be set as this on the context. It can be a good way to give your iterator function access to an object in cases where an ES6 arrow function would not be appropriate.

Usage Example:

let includesManager = people.any(this.findPersonInManagersList, this);

let includesStockHolder = people.any(person => {
  return this.findPersonInStockHoldersList(person)
});

if (includesManager || includesStockHolder) {
  Paychecks.addBiggerBonus();
}

arrayContentDidChange (startIdx, removeAmt, addAmt) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:646

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.

let arr = [1, 2, 3, 4, 5];

arr.copyWithin(-2); // [1, 2, 3, 1, 2]
// arr.lastObject = 5
arr.arrayContentDidChange(3, 2, 2);
// arr.lastObject = 2

arrayContentWillChange (startIdx, removeAmt, addAmt) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:579

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.

import Component from '@ember/component';
import EmberObject from '@ember/object';

const Post = EmberObject.extend({
  body: '',
  save() {}
})

export default Component.extend({
  attemptsToModify: 0,
  successfulModifications: 0,
  posts: null,

  init() {
    this._super(...arguments);

    this.posts = [1, 2, 3].map(i => Post.create({ body: i }));
    this.posts.addArrayObserver(this, {
      willChange() {
        this.incrementProperty('attemptsToModify');
      },
      didChange() {
        this.incrementProperty('successfulModifications');
      }
    });
  },

  actions: {
    editPost(post, newContent) {
      let oldContent = post.body,
          postIndex = this.posts.indexOf(post);

      this.posts.arrayContentWillChange(postIndex, 0, 0); // attemptsToModify = 1
      post.set('body', newContent);

      post.save()
        .then(response => {
          this.posts.arrayContentDidChange(postIndex, 0, 0); // successfulModifications = 1
        })
        .catch(error => {
          post.set('body', oldContent);
        })
    }
  }
});

compact Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1367

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

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1095

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 Array.prototype.every() method defined in ES5.

The callback method should have the following signature:

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.

All params are optional. The method should return 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.

Usage example:

function isAdult(person) {
  return person.age > 18;
};

const people = Ember.A([{ name: 'John', age: 24 }, { name: 'Joan', age: 45 }]);
const areAllAdults = people.every(isAdult);

filter (callback, target) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:845

callback

Function

The callback to execute

target

Object

The target object to use

returns

Array

A filtered array.

Returns a new array with all of the items in the enumeration that the provided callback function returns true for. This method corresponds to Array.prototype.filter().

The callback method should have the following signature:

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.

All parameters are optional. The function should return true to include the item in the results, and false otherwise.

Example:

function isAdult(person) {
  return person.age > 18;
};

let people = Ember.A([{ name: 'John', age: 14 }, { name: 'Joan', age: 45 }]);

people.filter(isAdult); // returns [{ name: 'Joan', age: 45 }];

Note that in addition to a callback, you can 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. For example:

function isAdultAndEngineer(person) {
  return person.age > 18 && this.engineering;
}

class AdultsCollection {
  engineering = false;

  constructor(opts = {}) {
    super(...arguments);

    this.engineering = opts.engineering;
    this.people = Ember.A([{ name: 'John', age: 14 }, { name: 'Joan', age: 45 }]);
  }
}

let collection = new AdultsCollection({ engineering: true });
collection.people.filter(isAdultAndEngineer, { target: collection });

filterBy (key, value) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:965

key

String

the property to test

value

*

optional value to test against.

returns

Array

filtered array

Filters the array by the property and an optional value. If a value is given, it returns the items that have said value for the property. If not, it returns all the items that have a truthy value for the property.

Example Usage:

let things = Ember.A([{ food: 'apple', isFruit: true }, { food: 'beans', isFruit: false }]);

things.filterBy('food', 'beans'); // [{ food: 'beans', isFruit: false }]
things.filterBy('isFruit'); // [{ food: 'apple', isFruit: true }]

find (callback, target) Object public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1016

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):

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.

Example Usage:

let users = [
  { id: 1, name: 'Yehuda' },
  { id: 2, name: 'Tom' },
  { id: 3, name: 'Melanie' },
  { id: 4, name: 'Leah' }
];

users.find((user) => user.name == 'Tom'); // [{ id: 2, name: 'Tom' }]
users.find(({ id }) => id == 3); // [{ id: 3, name: 'Melanie' }]

findBy (key, value) Object public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1063

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.

Usage Example:

let users = [
  { id: 1, name: 'Yehuda', isTom: false },
  { id: 2, name: 'Tom', isTom: true },
  { id: 3, name: 'Melanie', isTom: false },
  { id: 4, name: 'Leah', isTom: false }
];

users.findBy('id', 4); // { id: 4, name: 'Leah', isTom: false }
users.findBy('name', 'Melanie'); // { id: 3, name: 'Melanie', isTom: false }
users.findBy('isTom'); // { id: 2, name: 'Tom', isTom: true }

forEach (callback, target) Object public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:674

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):

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.

Example Usage:

let foods = [
  { name: 'apple', eaten: false },
  { name: 'banana', eaten: false },
  { name: 'carrot', eaten: false }
];

foods.forEach((food) => food.eaten = true);

let output = '';
foods.forEach((item, index, array) =>
  output += `${index + 1}/${array.length} ${item.name}\n`;
);
console.log(output);
// 1/3 apple
// 2/3 banana
// 3/3 carrot

getEach (key) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:734

key

String

name of the property

returns

Array

The mapped array.

Alias for mapBy.

Returns the value of the named property on all items in the enumeration.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.getEach('name');
// ['Joe', 'Matt'];

people.getEach('nonexistentProperty');
// [undefined, undefined];

includes (object, startAt) Boolean public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1383

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.

Used to determine if the array contains the passed object. Returns true if found, false otherwise.

The optional startAt argument can be used to pass a starting index to search from, effectively slicing the searchable portion of the array. If it's negative it will add the array length to the startAt value passed in as the index to search from. If less than or equal to -1 * array.length the entire array is searched.

This method has the same behavior of JavaScript's Array.includes.

[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

indexOf (object, startAt) Number public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:383

object

Object

the item to search for

startAt

Number

optional starting location to search, default 0

returns

Number

index or -1 if not found

Used to determine the passed object's first occurrence in the array. Returns the index if found, -1 if no match is found.

The optional startAt argument can be used to pass a starting index to search from, effectively slicing the searchable portion of the array. If it's negative it will add the array length to the startAt value passed in as the index to search from. If less than or equal to -1 * array.length the entire array is searched.

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, equivalent to indexOf('a', 4)
arr.indexOf('a', -100); //  0, searches entire array
arr.indexOf('b', 3);    // -1
arr.indexOf('a', 100);  // -1

let people = [{ name: 'Zoey' }, { name: 'Bob' }]
let newPerson = { name: 'Tom' };
people = [newPerson, ...people, newPerson];

people.indexOf(newPerson);     //  0
people.indexOf(newPerson, 1);  //  3
people.indexOf(newPerson, -4); //  0
people.indexOf(newPerson, 10); // -1

invoke (methodName, args) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1317

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.

class Person {
  name = null;

  constructor(name) {
    this.name = name;
  }

  greet(prefix='Hello') {
    return `${prefix} ${this.name}`;
  }
}

let people = [new Person('Joe'), new Person('Matt')];

people.invoke('greet'); // ['Hello Joe', 'Hello Matt']
people.invoke('greet', 'Bonjour'); // ['Bonjour Joe', 'Bonjour Matt']

isAny (key, value) Boolean public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1223

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.

Example usage:

const food = [
  { food: 'apple', isFruit: true },
  { food: 'bread', isFruit: false },
  { food: 'banana', isFruit: true }
];

food.isAny('isFruit'); // true

isEvery (key, value) Boolean public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1137

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.

class Language {
  constructor(name, isProgrammingLanguage) {
    this.name = name;
    this.programmingLanguage = isProgrammingLanguage;
  }
}

const compiledLanguages = [
  new Language('Java', true),
  new Language('Go', true),
  new Language('Rust', true)
]

const languagesKnownByMe = [
  new Language('Javascript', true),
  new Language('English', false),
  new Language('Ruby', true)
]

compiledLanguages.isEvery('programmingLanguage'); // true
languagesKnownByMe.isEvery('programmingLanguage'); // false

lastIndexOf (object, startAt) Number public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:425

object

Object

the item to search for

startAt

Number

optional starting location to search from backwards, defaults to `(array.length - 1)`

returns

Number

The last index of the `object` in the array 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 greater than or equal to the length of the array, the search starts from the last position.
• If it's negative, it is taken as the offset from the end of the array i.e. startAt + array.length.
• If it's any other positive number, will search backwards from that index of the array.

Returns -1 if no match is found.

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('a', -3);   //  0
arr.lastIndexOf('b', 3);    //  1
arr.lastIndexOf('a', 100);  //  4

map (callback, target) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:780

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, array);
let arr = [1, 2, 3, 4, 5, 6];

arr.map(element => element * element);
// [1, 4, 9, 16, 25, 36];

arr.map((element, index) => element + index);
// [1, 3, 5, 7, 9, 11];

• 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.

mapBy (key) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:824

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.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.mapBy('name');
// ['Joe', 'Matt'];

people.mapBy('unknownProperty');
// [undefined, undefined];

objectAt (idx) * public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:234

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.

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

objectsAt (indexes) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:259

indexes

Array

An array of indexes of items to return.

returns

Array

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

let arr = ['a', 'b', 'c', 'd'];

arr.objectsAt([0, 1, 2]);  // ['a', 'b', 'c']
arr.objectsAt([2, 3, 4]);  // ['c', 'd', undefined]

reduce (callback, initialValue) Object public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1251

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 array into a single value. It is a useful way to collect a summary value from an array. 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, 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.

Example Usage:

  let numbers = [1, 2, 3, 4, 5];

  numbers.reduce(function(summation, current) {
    return summation + current;
  }); // 15 (1 + 2 + 3 + 4 + 5)

  numbers.reduce(function(summation, current) {
    return summation + current;
  }, -15); // 0 (-15 + 1 + 2 + 3 + 4 + 5)


  let binaryValues = [true, false, false];

  binaryValues.reduce(function(truthValue, current) {
    return truthValue && current;
  }); // false (true && false && false)

reject (callback, target) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:918

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, 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.

Example Usage:

const food = [
  { food: 'apple', isFruit: true },
  { food: 'bread', isFruit: false },
  { food: 'banana', isFruit: true }
];
const nonFruits = food.reject(function(thing) {
  return thing.isFruit;
}); // [{food: 'bread', isFruit: false}]

rejectBy (key, value) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:989

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 the provided key. You can pass an optional second argument with a target value to reject for the key. Otherwise this will reject objects where the provided property evaluates to false.

Example Usage:

  let food = [
    { name: "apple", isFruit: true },
    { name: "carrot", isFruit: false },
    { name: "bread", isFruit: false },
  ];
  food.rejectBy('isFruit'); // [{ name: "carrot", isFruit: false }, { name: "bread", isFruit: false }]
  food.rejectBy('name', 'carrot'); // [{ name: "apple", isFruit: true }}, { name: "bread", isFruit: false }]

removeArrayObserver (target, opts) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:536

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.

setEach (key, value) Object public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:757

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.

let people = [{name: 'Joe'}, {name: 'Matt'}];

people.setEach('zipCode', '10011');
// [{name: 'Joe', zipCode: '10011'}, {name: 'Matt', zipCode: '10011'}];

slice (beginIndex, endIndex) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:343

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.

let arr = ['red', 'green', 'blue'];

arr.slice(0);       // ['red', 'green', 'blue']
arr.slice(0, 2);    // ['red', 'green']
arr.slice(1, 100);  // ['green', 'blue']

sortBy (property) Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1416

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.

   let colors = [
 { name: 'red', weight: 500 },
 { name: 'green', weight: 600 },
 { name: 'blue', weight: 500 }
];

   colors.sortBy('name');
   // [{name: 'blue', weight: 500}, {name: 'green', weight: 600}, {name: 'red', weight: 500}]

   colors.sortBy('weight', 'name');
   // [{name: 'blue', weight: 500}, {name: 'red', weight: 500}, {name: 'green', weight: 600}]

toArray Array public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1355

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.

uniq EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1460

returns

EmberArray

Returns a new array 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 (key) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1479

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.

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];

without (value) EmberArray public

Defined in packages/@ember/-internals/runtime/lib/mixins/array.js:1501

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.

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