# UnorderedSet

[**collections/unordered-set**](/near-sdk-js/collections/unordered-set.md) • **Docs**

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[near-sdk-js v2.0.0](/near-sdk-js/packages.md) / [collections/unordered-set](/near-sdk-js/collections/unordered-set.md) / UnorderedSet

## Class: UnorderedSet\<DataType>

An unordered set that stores data in NEAR storage.

### Type Parameters

• **DataType**

### Constructors

#### new UnorderedSet()

> **new UnorderedSet**<`DataType`>(`prefix`): [`UnorderedSet`](/near-sdk-js/collections/unordered-set/classes/unorderedset.md)<`DataType`>

**Parameters**

• **prefix**: `string`

The byte prefix to use when storing elements inside this collection.

**Returns**

[`UnorderedSet`](/near-sdk-js/collections/unordered-set/classes/unorderedset.md)<`DataType`>

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:35](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L35)

### Properties

#### \_elements

> `readonly` **\_elements**: [`Vector`](/near-sdk-js/collections/vector/classes/vector.md)<`DataType`>

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:30](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L30)

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#### elementIndexPrefix

> `readonly` **elementIndexPrefix**: `string`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:29](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L29)

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#### prefix

> `readonly` **prefix**: `string`

The byte prefix to use when storing elements inside this collection.

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:35](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L35)

### Accessors

#### length

> `get` **length**(): `number`

The number of elements stored in the collection.

**Returns**

`number`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:43](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L43)

### Methods

#### \[iterator]\()

> **\[iterator]**(): [`VectorIterator`](/near-sdk-js/collections/vector/classes/vectoriterator.md)<`DataType`>

**Returns**

[`VectorIterator`](/near-sdk-js/collections/vector/classes/vectoriterator.md)<`DataType`>

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:157](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L157)

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#### clear()

> **clear**(`options`?): `void`

Remove all of the elements stored within the collection.

**Parameters**

• **options?**: `Pick`<[`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>, `"serializer"`>

**Returns**

`void`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:147](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L147)

***

#### contains()

> **contains**(`element`, `options`?): `boolean`

Checks whether the collection contains the value.

**Parameters**

• **element**: `DataType`

The value for which to check the presence.

• **options?**: `Pick`<[`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>, `"serializer"`>

Options for storing data.

**Returns**

`boolean`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:60](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L60)

***

#### elements()

> **elements**(`__namedParameters`): `DataType`\[]

**Parameters**

• **\_\_namedParameters**

• **\_\_namedParameters.limit?**: `number`

• **\_\_namedParameters.options?**: [`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>

• **\_\_namedParameters.start?**: `number`

**Returns**

`DataType`\[]

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:230](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L230)

***

#### extend()

> **extend**(`elements`): `void`

Extends the current collection with the passed in array of elements.

**Parameters**

• **elements**: `DataType`\[]

The elements to extend the collection with.

**Returns**

`void`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:196](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L196)

***

#### isEmpty()

> **isEmpty**(): `boolean`

Checks whether the collection is empty.

**Returns**

`boolean`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:50](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L50)

***

#### remove()

> **remove**(`element`, `options`?): `boolean`

Returns true if the element was present in the set.

**Parameters**

• **element**: `DataType`

The entry to remove.

• **options?**: [`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>

Options for retrieving and storing data.

**Returns**

`boolean`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:101](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L101)

***

#### serialize()

> **serialize**(`options`?): `Uint8Array`

Serialize the collection.

**Parameters**

• **options?**: `Pick`<[`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>, `"serializer"`>

Options for storing the data.

**Returns**

`Uint8Array`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:207](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L207)

***

#### set()

> **set**(`element`, `options`?): `boolean`

If the set did not have this value present, `true` is returned. If the set did have this value present, `false` is returned.

**Parameters**

• **element**: `DataType`

The value to store in the collection.

• **options?**: `Pick`<[`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>, `"serializer"`>

Options for storing the data.

**Returns**

`boolean`

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:76](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L76)

***

#### toArray()

> **toArray**(`options`?): `DataType`\[]

Return a JavaScript array of the data stored within the collection.

**Parameters**

• **options?**: [`GetOptions`](/near-sdk-js/types/collections/interfaces/getoptions.md)<`DataType`>

Options for retrieving and storing the data.

**Returns**

`DataType`\[]

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:179](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L179)

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#### reconstruct()

> `static` **reconstruct**<`DataType`>(`data`): [`UnorderedSet`](/near-sdk-js/collections/unordered-set/classes/unorderedset.md)<`DataType`>

Converts the deserialized data from storage to a JavaScript instance of the collection.

**Type Parameters**

• **DataType**

**Parameters**

• **data**: [`UnorderedSet`](/near-sdk-js/collections/unordered-set/classes/unorderedset.md)<`DataType`>

The deserialized data to create an instance from.

**Returns**

[`UnorderedSet`](/near-sdk-js/collections/unordered-set/classes/unorderedset.md)<`DataType`>

**Defined in**

[packages/near-sdk-js/src/collections/unordered-set.ts:216](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/collections/unordered-set.ts#L216)


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