The proposal based on really worst thing in JavaScript Arrays. If i as developer want to make declarative code with combination of `Array#map`, `Array#filter` or `Array#reduce` - i will take a lot of iterations (count of chain element will determinate count of iterations).
```js const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]; const newArr = arr .map(a => a + 1) .filter(a => a % 2 === 0) .filter((a, i) => i < 3); // [2, 4, 6], but 3 iterations across `arr` ``` So, my proposal is: add lazy iterator with additional functions which help to use declarative collection method in chain as "zero-abstraction" and will iterate only once (will not be related to count of chain methods). Actually, i've already created implementation and usage of this implementation looks like this: ```js const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]; const newArr = arr .lazy() .map(a => a + 1) .filter(a => a % 2 === 0) .take(3) .collect(); // [ 2, 4, 6 ], but 1 iterations across `arr` ``` And, actually, current implementation could be used with all `Iterable` objects, if this object will implement method `fromIterator` (it's needed for `LazyIterator#collect` method).
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