What is an enumerated argument in Object.create?

Question

In what cases do you want enumerable to set enumerable to true ?

Answer 1

The property of an object must be enumerable if you want to have access to it when re-executing all the properties of objects. Example:

 var obj = {prop1: 'val1', prop2:'val2'}; for (var prop in obj){ console.log(prop, obj[prop]); } 

In this type of instantiation, the enumerable is always true, this will give you the result:

 prop1 val1 prop2 val2 

If you used Object.create () as follows:

 obj = Object.create({}, { prop1: { value: 'val1', enumerable: true}, prop2: { value: 'val2', enumerable: false} }); 

your for loop will only have access to prop1, not prop2. Using Object.create (), properties are set with enumerable = false by default.