Best of Modern JavaScript — Iterable Objects

Special properties of iterable objects.

Since 2015, JavaScript has improved immensely.

It’s much more pleasant to use it now than ever.

In this article, we’ll look at JavaScript iterable objects.

Iterable Computed Data

Iterable content can come from computed data.

Methods can return iterable objects that we can iterate through.

We have 3 methods that return iterable objects. They include the entries , keys , and values method.

entries returns an iterable over the entries encoded as key-value arrays.

For arrays, the keys are indexes and the values are the elements.

For sets, the keys and values are both the elements.

keys returns an iterable object with the keys of the entries.

values returns an iterable object with the values of the entries.

For instance, we can write:

const arr = ['foo', 'bar', 'baz'];
for (const [key, value] of arr.entries()) {
  console.log(key, value);
}

Then we get:

0 "foo"
1 "bar"
2 "baz"

logged.

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