JavaScript: Lazy collections

Here you need to build a lazy collection.

enumerable.js

Implement and export as default a class handling collections of objects. The main feature of this class is that it uses lazy processing.

import Enumerable from './enumerable.js';

const elements = [
  { key: 'value' },
  { key: '' },
];
const coll = Enumerable.wrap(elements);
const result = coll.where('key', 'value');

result.all() // [{ key: 'value' }]

Tips

• The usage examples are given in more detail in the tests
• Advanced challenge: add the allWithMemoization() method implementing memoization and test it by running the make test-memo command in the exercise terminal <!-- * Ленивые коллекции -->