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JavaScript Iterables

Iterables are iterable objects (like Arrays).

Iterables can be accessed with simple and efficient code.

Iterables can be iterated over with for..of loops

The For Of Loop

The JavaScript for..of statement loops through the elements of an iterable object.

Syntax

for (variable of iterable) {
  // code block to be executed
}

Iterating

Iterating is easy to understand.

It simply means looping over a sequence of elements.

Here are some easy examples:

  • Iterating over a String
  • Iterating over an Array

Iterating Over a String

You can use a for..of loop to iterate over the elements of a string:

Example

const name = "W3Schools";

for (const x of name) {
  // code block to be executed
}
Try it Yourself »

Iterating Over an Array

You can use a for..of loop to iterate over the elements of an Array:

Example

const letters = ["a","b","c"];

for (const x of letters) {
  // code block to be executed
}
Try it Yourself »

You can learn more details about Iterables in the chapter JS Object Iterables.



Iterating Over a Set

You can use a for..of loop to iterate over the elements of a Set:

Example

const letters = new Set(["a","b","c"]);

for (const x of letters) {
  // code block to be executed
}
Try it Yourself »

Sets and Maps are covered in the next chapters.

Iterating Over a Map

You can use a for..of loop to iterate over the elements of a Map:

Example

const fruits = new Map([
  ["apples", 500],
  ["bananas", 300],
  ["oranges", 200]
]);

for (const x of fruits) {
  // code block to be executed
}
Try it Yourself »