# ObservableSingleBindChain

interface

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1267)

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## Type parameters

### `TKey: extends string`

### `TVal`

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## Methods

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### `to( observable, key ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1281)

#### Type parameters

* * `O`
  * `K`

#### Parameters

* `observable: O`
* `key: K`

#### Returns

* `void`

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### `to( observable1, observable2, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1290)

#### Type parameters

* * `O1: extends Observable & { [ P in string ]?: any }`
  * `O2: extends Observable & { [ P in string ]?: any }`

#### Parameters

* `observable1: O1`
* `observable2: O2`
* `callback: ( value1: O1[ TKey ], value2: O2[ TKey ] ) => TVal`

#### Returns

* `void`

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### `to( observable1, observable2, observable3, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1310)

#### Type parameters

* * `O1: extends Observable & { [ P in string ]?: any }`
  * `O2: extends Observable & { [ P in string ]?: any }`
  * `O3: extends Observable & { [ P in string ]?: any }`

#### Parameters

* `observable1: O1`
* `observable2: O2`
* `observable3: O3`
* `callback: ( value1: O1[ TKey ], value2: O2[ TKey ], value3: O3[ TKey ] ) => TVal`

#### Returns

* `void`

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### `to( observable1, observable2, observable3, observable4, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1336)

#### Type parameters

* * `O1: extends Observable & { [ P in string ]?: any }`
  * `O2: extends Observable & { [ P in string ]?: any }`
  * `O3: extends Observable & { [ P in string ]?: any }`
  * `O4: extends Observable & { [ P in string ]?: any }`

#### Parameters

* `observable1: O1`
* `observable2: O2`
* `observable3: O3`
* `observable4: O4`
* `callback: ( value1: O1[ TKey ], value2: O2[ TKey ], value3: O3[ TKey ], value4: O4[ TKey ] ) => TVal`

#### Returns

* `void`

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### `to( observable1, observable2, observable3, observable4, observable5, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1368)

#### Type parameters

* * `O1: extends Observable & { [ P in string ]?: any }`
  * `O2: extends Observable & { [ P in string ]?: any }`
  * `O3: extends Observable & { [ P in string ]?: any }`
  * `O4: extends Observable & { [ P in string ]?: any }`
  * `O5: extends Observable & { [ P in string ]?: any }`

#### Parameters

* `observable1: O1`
* `observable2: O2`
* `observable3: O3`
* `observable4: O4`
* `observable5: O5`
* `callback: ( value1: O1[ TKey ], value2: O2[ TKey ], value3: O3[ TKey ], value4: O4[ TKey ], value5: O5[ TKey ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable1, key1, observable2, key2, observable3, key3, observable4, key4, observable5, key5, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1382)

#### Type parameters

* * `O1: extends Observable`
  * `K1`
  * `O2: extends Observable`
  * `K2`
  * `O3: extends Observable`
  * `K3`
  * `O4: extends Observable`
  * `K4`
  * `O5: extends Observable`
  * `K5`

#### Parameters

* `observable1: O1`
* `key1: K1`
* `observable2: O2`
* `key2: K2`
* `observable3: O3`
* `key3: K3`
* `observable4: O4`
* `key4: K4`
* `observable5: O5`
* `key5: K5`
* `callback: ( value1: O1[ K1 ], value2: O2[ K2 ], value3: O3[ K3 ], value4: O4[ K4 ], value5: O5[ K5 ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable1, key1, observable2, key2, observable3, key3, observable4, key4, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1348)

#### Type parameters

* * `O1: extends Observable`
  * `K1`
  * `O2: extends Observable`
  * `K2`
  * `O3: extends Observable`
  * `K3`
  * `O4: extends Observable`
  * `K4`

#### Parameters

* `observable1: O1`
* `key1: K1`
* `observable2: O2`
* `key2: K2`
* `observable3: O3`
* `key3: K3`
* `observable4: O4`
* `key4: K4`
* `callback: ( value1: O1[ K1 ], value2: O2[ K2 ], value3: O3[ K3 ], value4: O4[ K4 ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable1, key1, observable2, key2, observable3, key3, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1320)

#### Type parameters

* * `O1: extends Observable`
  * `K1`
  * `O2: extends Observable`
  * `K2`
  * `O3: extends Observable`
  * `K3`

#### Parameters

* `observable1: O1`
* `key1: K1`
* `observable2: O2`
* `key2: K2`
* `observable3: O3`
* `key3: K3`
* `callback: ( value1: O1[ K1 ], value2: O2[ K2 ], value3: O3[ K3 ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable1, key1, observable2, key2, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1298)

#### Type parameters

* * `O1: extends Observable`
  * `K1`
  * `O2: extends Observable`
  * `K2`

#### Parameters

* `observable1: O1`
* `key1: K1`
* `observable2: O2`
* `key2: K2`
* `callback: ( value1: O1[ K1 ], value2: O2[ K2 ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable, key, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1285)

#### Type parameters

* * `O: extends Observable`
  * `K`

#### Parameters

* `observable: O`
* `key: K`
* `callback: ( value: O[ K ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1277)

#### Type parameters

* `O: extends Observable & { [ P in string ]?: any }`

#### Parameters

* `observable: O`
* `callback: ( value: O[ TKey ] ) => TVal`

#### Returns

* `void`

<a id="function-to">

### `to( observable ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1274)

#### Type parameters

* `O`

#### Parameters

* `observable: O`

#### Returns

* `void`

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### `toMany( observables, key, callback ) → void`

[See source](https://github.com/ckeditor/ckeditor5/blob/master/packages/ckeditor5-utils/src/observablemixin.ts#L1268)

#### Type parameters

* * `O: extends Observable`
  * `K`

#### Parameters

* `observables: readonly Array<O>`
* `key: K`
* `callback: ( values: Array<O[ K ]> ) => TVal`

#### Returns

* `void`

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Full index of the CKEditor 5 API reference: [llms.txt](llms.txt)