---
id: fast-foundation.resolverbuilder.singleton
title: ResolverBuilder.singleton() method
hide_title: true
---
<!-- Do not edit this file. It is automatically generated by API Documenter. -->

[@microsoft/fast-foundation](./fast-foundation.md) &gt; [ResolverBuilder](./fast-foundation.resolverbuilder.md) &gt; [singleton](./fast-foundation.resolverbuilder.singleton.md)

## ResolverBuilder.singleton() method

Creates a resolver that enforces a singleton lifetime.

<b>Signature:</b>

```typescript
singleton(value: Constructable): Resolver<K>;
```

## Parameters

|  Parameter | Type | Description |
|  --- | --- | --- |
|  value | [Constructable](./fast-element.constructable.md) | The type to create and cache the singleton for. |

<b>Returns:</b>

[Resolver](./fast-foundation.resolver.md)<!-- -->&lt;K&gt;

The resolver.
