Enumeration and Object Oriented JavaScript

• [ Introduction ]
• [ DontEnum ]
• [ Prototype Chain ]
• [ Create a Subclass ]
• Set DontEnum
• [ Borrowing ]
• [ Shadowing ]
• [ Borrowing Solution ]
• [ Enumerate Using Array? ]
• [ propertyIsEnumerable ]
• [ Modifying Properties ]
• [ Conclusion ]

 

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How to set the DontEnum attribute

You can't.

The fact that DontEnum is not settable is a problem that is positively addressed in ECMAScript 4.

// Make a property have the DontEnum attribute.
	myObj.propertyIsEnumerable("toString", false);

Nothing will force IE to properly recognize the DontEnum attribute. However, we can explicitly check certain properties to see if they exist. All user-created properties in ES3 are enumerable.

If you want a generic object with a non-enumerable constructor property, the way to do that is through creating a function.

var o = Function().prototype;