# replace

`import { replace } from "destack:memory";`

Replace `destination` and return its previous value.

```ds title="replace"
export declare function replace<T>(destination: &'a exclusive T, value: T): T
```

[language/library/src/memory/replace.ds:5](https://github.com/destack-sh/destack/blob/main/language/library/src/memory/replace.ds#L5)