[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Type](https://evolu.dev/docs/api-reference/common/Type) › ObjectUnexpectedPrototypeError

Defined in: [packages/common/src/Type.ts:11350](https://github.com/evoluhq/evolu/blob/f0109fb501a593010e858e39248dde1200eeb2d7/packages/common/src/Type.ts#L11350)

An error returned when an [object](https://evolu.dev/docs/api-reference/common/Type/functions/object) input falls outside its supported
plain-object prototype boundary.

Object Types use the realm-neutral structural heuristic described by
[isPlainObject](https://evolu.dev/docs/api-reference/common/Object/functions/isPlainObject). Values that do not satisfy it return this error instead
of having their prototype or inherited state discarded. `reason.value` is the
rejected object.

## Extends

- [`TypeError`](https://evolu.dev/docs/api-reference/common/Type/interfaces/TypeError)\<`"Object"`\>

## Properties

<a id="reason"></a>

### reason

```ts
readonly reason: {
  kind: "UnexpectedPrototype";
  value: object;
};
```

Defined in: [packages/common/src/Type.ts:11351](https://github.com/evoluhq/evolu/blob/f0109fb501a593010e858e39248dde1200eeb2d7/packages/common/src/Type.ts#L11351)

| Name    | Type                    | Defined in                                                                                                                                             |
| ------- | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `kind`  | `"UnexpectedPrototype"` | [packages/common/src/Type.ts:11352](https://github.com/evoluhq/evolu/blob/f0109fb501a593010e858e39248dde1200eeb2d7/packages/common/src/Type.ts#L11352) |
| `value` | `object`                | [packages/common/src/Type.ts:11353](https://github.com/evoluhq/evolu/blob/f0109fb501a593010e858e39248dde1200eeb2d7/packages/common/src/Type.ts#L11353) |

---

<a id="type"></a>

### type

```ts
readonly type: "Object";
```

Defined in: [packages/common/src/Type.ts:870](https://github.com/evoluhq/evolu/blob/f0109fb501a593010e858e39248dde1200eeb2d7/packages/common/src/Type.ts#L870)

#### Inherited from

[`TypeError`](https://evolu.dev/docs/api-reference/common/Type/interfaces/TypeError).[`type`](https://evolu.dev/docs/api-reference/common/Type/interfaces/TypeError#type)