Appendix C. Built-in Objects

This Appendix lists the built-in constructor functions outlined in the ECMAScript standard, together with the properties and methods of the objects created by these constructors.


Object() is a constructor that creates objects, for example:

>>> var o = new Object();

This is the same as using the object literal:

>>> var o = {}; // recommended

You can pass anything to the constructor and it will try to guess what it is and use a more appropriate constructor. For example, passing a string to new Object() will be the same as using the new String() constructor. This is not a recommended practise, but still possible.

>>> var o = new Object('something');
>>> o.constructor


>>> var o = new Object(123); >>> o.constructor ...

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