--- editUrl: false next: false prev: false title: "single" --- > **single**\<`T`\>(`cb`): () => `T` @__PURE__ ## Type parameters • **T** ## Parameters • **cb** ## Returns `Function` ### Returns `T` ## Since 2.0.0. Creates a singleton object. ## Source [src/core/ioc/dependency-injection.ts:11](https://github.com/sern-handler/handler/blob/a19edaf8838dcf088d3947f4a6aa6213d8f5bb9e/src/core/ioc/dependency-injection.ts#L11)