JS: Enumerable Property

What is Enumerable Property

A Enumerable Property is a property whose Property Attribute enumerable is true.

Purpose of Enumerable Attribute

It indicates whether the property is part of a list kind of thing.

Many loop or iteration functions going thru object properties will only list the property if it is enumerable.

For example, Array has a property length, which has enumerable attribute false.

Note: basically, the enumerable attribute is just bad design of JavaScript. It is the result of mixing array, dictionary, and struct, types into one.

Check If Property is Enumerable

• JS: Object.prototype.propertyIsEnumerable ❌
• JS: Reflect.getOwnPropertyDescriptor