Iterator

Summary

The Iterator function returns an object which implements legacy iterator protocol and iterates over enumerable properties of an object.

Syntax

Iterator(object)

Parameters

object

Object to iterate over properties.

Description

An overview of the usage is available on the Iterators and Generators page.

Methods

Iterator.prototype.next

Returns next item in the [property_name, property_value] format. It throws StopIteration if there are no more items.

Examples

Iterating over properties of an object

var a = {
  x: 10,
  y: 20,
};
var iter = Iterator(a);
console.log(iter.next()); // ["x", 10]
console.log(iter.next()); // ["y", 20]
console.log(iter.next()); // throws StopIteration

Iterating over properties of an object with legacy destructuring for-in statement

var a = {
  x: 10,
  y: 20,
};

for (var [name, value] in Iterator(a)) {
  console.log(name, value);   // x 10
                              // y 20
}

Specifications

Non-standard. Not part of any current standards document.

Browser compatibility

See also

• Iterators and Generators
• StopIteration