Class Ember.NativeArray

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

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

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.

Adds each object in the passed enumerable to the receiver.

Adds an observer on a property.

This is the core method used to register an observer for a property.

Once you call this method, any time the key's value is set, your observer will be notified. Note that the observers are triggered any time the value is set, regardless of whether it has actually changed. Your observer should be prepared to handle that.

Observer Methods

Observer methods have the following signature:

import Component from '@ember/component';

export default Component.extend({
  init() {
    this._super(...arguments);
    this.addObserver('foo', this, 'fooDidChange');
  },

  fooDidChange(sender, key, value, rev) {
    // your code
  }
});

The sender is the object that changed. The key is the property that changes. The value property is currently reserved and unused. The rev is the last property revision of the object when it changed, which you can use to detect if the key value has really changed or not.

Usually you will not need the value or revision parameters at the end. In this case, it is common to write observer methods that take only a sender and key value as parameters or, if you aren't interested in any of these values, to write an observer that has no parameters at all.

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();
}

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.

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.

Returns the cached value of a computed property, if it exists. This allows you to inspect the value of a computed property without accidentally invoking it if it is intended to be generated lazily.

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

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

colors.length;  // 3
colors.clear(); // []
colors.length;  // 0

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

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

Set the value of a property to the current value minus some amount.

player.decrementProperty('lives');
orc.decrementProperty('health', 5);

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();
}

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.

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.

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.

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.

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.

Retrieves the value of a property from the object.

This method is usually similar to using object[keyName] or object.keyName, however it supports both computed properties and the unknownProperty handler.

Because get unifies the syntax for accessing all these kinds of properties, it can make many refactorings easier, such as replacing a simple property with a computed property, or vice versa.

Computed Properties

Computed properties are methods defined with the property modifier declared at the end, such as:

fullName: Ember.computed('firstName', 'lastName', function() {
  return this.get('firstName') + ' ' + this.get('lastName');
})

When you call get on a computed property, the function will be called and the return value will be returned instead of the function itself.

Unknown Properties

Likewise, if you try to call get on a property whose value is undefined, the unknownProperty() method will be called on the object. If this method returns any value other than undefined, it will be returned instead. This allows you to implement "virtual" properties that are not defined upfront.

Alias for mapBy

To get the values of multiple properties at once, call getProperties with a list of strings or an array:

record.getProperties('firstName', 'lastName', 'zipCode');
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

is equivalent to:

record.getProperties(['firstName', 'lastName', 'zipCode']);
// { firstName: 'John', lastName: 'Doe', zipCode: '10011' }

Retrieves the value of a property, or a default value in the case that the property returns undefined.

person.getWithDefault('lastName', 'Doe');

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

Set the value of a property to the current value plus some amount.

person.incrementProperty('age');
team.incrementProperty('score', 2);

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.

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

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

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

colors.insertAt(2, 'yellow');  // ['red', 'green', 'yellow', 'blue']
colors.insertAt(5, 'orange');  // Error: Index out of range

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

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.

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.

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.

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

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.

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

Convenience method to call propertyWillChange and propertyDidChange in succession.

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

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]

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

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

colors.popObject();   // 'blue'
console.log(colors);  // ['red', 'green']

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

let colors = ['red', 'green'];

colors.pushObject('black');     // ['red', 'green', 'black']
colors.pushObject(['yellow']);  // ['red', 'green', ['yellow']]

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

let colors = ['red'];

colors.pushObjects(['yellow', 'orange']);  // ['red', 'yellow', 'orange']

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.

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.

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.

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.

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 OUT_OF_RANGE_EXCEPTION.

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

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.

Removes each object in the passed enumerable from the receiver.

Remove an observer you have previously registered on this object. Pass the same key, target, and method you passed to addObserver() and your target will no longer receive notifications.

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

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

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

Sets the provided key or path to the value.

record.set("key", value);

This method is generally very similar to calling object["key"] = value or object.key = value, except that it provides support for computed properties, the setUnknownProperty() method and property observers.

Computed Properties

If you try to set a value on a key that has a computed property handler defined (see the get() method for an example), then set() will call that method, passing both the value and key instead of simply changing the value itself. This is useful for those times when you need to implement a property that is composed of one or more member properties.

Unknown Properties

If you try to set a value on a key that is undefined in the target object, then the setUnknownProperty() handler will be called instead. This gives you an opportunity to implement complex "virtual" properties that are not predefined on the object. If setUnknownProperty() returns undefined, then set() will simply set the value on the object.

Property Observers

In addition to changing the property, set() will also register a property change with the object. Unless you have placed this call inside of a beginPropertyChanges() and endPropertyChanges(), any "local" observers (i.e. observer methods declared on the same object), will be called immediately. Any "remote" observers (i.e. observer methods declared on another object) will be placed in a queue and called at a later time in a coalesced manner.

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.

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

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

colors.setObjects(['black', 'white']);  // ['black', 'white']
colors.setObjects([]);                  // []

Sets a list of properties at once. These properties are set inside a single beginPropertyChanges and endPropertyChanges batch, so observers will be buffered.

record.setProperties({ firstName: 'Charles', lastName: 'Jolley' });

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

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

colors.shiftObject();  // 'red'
console.log(colors);   // ['green', 'blue']

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']

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.

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

Set the value of a boolean property to the opposite of its current value.

starship.toggleProperty('warpDriveEngaged');

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.

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' }]

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

let colors = ['red'];

colors.unshiftObject('yellow');    // ['yellow', 'red']
colors.unshiftObject(['black']);   // [['black'], 'yellow', 'red']

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

let colors = ['red'];

colors.unshiftObjects(['black', 'white']);   // ['black', 'white', 'red']
colors.unshiftObjects('yellow'); // Type Error: 'undefined' is not a function

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']