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# Interface: WritableStreamDefaultController

[internal](../modules/internal-10.md).WritableStreamDefaultController

This Streams API interface represents a controller allowing control of a WritableStream's state. When constructing a WritableStream, the underlying sink is given a corresponding WritableStreamDefaultController instance to manipulate.

[MDN Reference](https://developer.mozilla.org/docs/Web/API/WritableStreamDefaultController)

## Properties

### signal

• `Readonly` **signal**: `AbortSignal`

[MDN Reference](https://developer.mozilla.org/docs/Web/API/WritableStreamDefaultController/signal)

#### Defined in

docs-util/node_modules/typescript/lib/lib.dom.d.ts:26043

## Methods

### error

▸ **error**(`e?`): `void`

[MDN Reference](https://developer.mozilla.org/docs/Web/API/WritableStreamDefaultController/error)

#### Parameters

| Name | Type |
| :------ | :------ |
| `e?` | `any` |

#### Returns

`void`

#### Defined in

docs-util/node_modules/typescript/lib/lib.dom.d.ts:26045