# allowUnknown

## Effect

By default, `object` doesn't allow unknown keys exist. If you want unknown keys to be allowed, you can call `allowKnown`.

## Arguments

None

## Example

```javascript
const schema1 = racoon.object({
  name: racoon.string()
});
schema1.validate({ name: 'Jack' }); // pass
schema1.validate({ name: 'Jack', age: 22 }); // fail

const schema1 = racoon.object({
  name: racoon.string()
}).allowUnknown();
schema1.validate({ name: 'Jack' }); // pass
schema1.validate({ name: 'Jack', age: 22 }); // pass
```