Can a variable be made readonly in Node.js

Question

I want to prevent a variable from being changed. Specifically a property of an Object: ``` var foo = { bar: 'baz' }; // do something to foo to make it readonly foo.bar = 'boing'; // should throw exception ``` Can this be done?

Accepted Answer

You could try

```
Object.defineProperty(foo, "bar", { writable: false });
```

and the later assignment either fails silently or, if you are in strict mode, throws an exception (according to David Flanagan's "JavaScript : The Definitive Guide" ).

Can a variable be made readonly in Node.js

Solution

Problem