Deprecation Guide for Deprecation of @ember/array Read Methods

All read-only methods and computed properties from @ember/array are deprecated. You should use native JavaScript array methods and properties instead. This guide covers the common read-only APIs and their native equivalents.

firstObject and lastObject

These computed properties provided safe access to the first and last elements of an array.

Before

import { A } from '@ember/array';
let arr = A(['a', 'b', 'c']);
let first = arr.get('firstObject'); // 'a'
let last = arr.get('lastObject');   // 'c'

After Use native array bracket notation, or the at() method for accessing elements from the end of the array.

let arr = ['a', 'b', 'c'];
let first = arr[0];
let last = arr.at(-1);

objectAt and objectsAt

These methods provided safe, index-based access to array elements.

Before

import { A } from '@ember/array';
let arr = A(['a', 'b', 'c']);
let middle = arr.objectAt(1);     // 'b'
let some = arr.objectsAt([0, 2]); // ['a', 'c']

After Use native array bracket notation for objectAt. For objectsAt, you can use map.

let arr = ['a', 'b', 'c'];
let middle = arr[1];
let some = [0, 2].map(index => arr[index]);

mapBy, filterBy, rejectBy, findBy

These methods were shortcuts for common mapping and filtering operations on arrays of objects.

Before

import { A } from '@ember/array';
let users = A([
  { name: 'John', isActive: true },
  { name: 'Jane', isActive: false },
]);
let names = users.mapBy('name');
let active = users.filterBy('isActive', true);
let john = users.findBy('name', 'John');

After Use the native map, filter, and find methods with arrow functions.

let users = [
  { name: 'John', isActive: true },
  { name: 'Jane', isActive: false },
];
let names = users.map(user => user.name);
let active = users.filter(user => user.isActive === true);
let john = users.find(user => user.name === 'John');

uniqBy

uniqBy created a new array with unique elements based on a property.

Before

import { uniqBy } from '@ember/array';
let users = [{ id: 1 }, { id: 2 }, { id: 1 }];
let unique = uniqBy(users, 'id');

After Use a Map to efficiently create a unique list.

let users = [{ id: 1 }, { id: 2 }, { id: 1 }];
let unique = Array.from(
  users.reduce((map, user) => map.set(user.id, user), new Map()).values()
);