> For the complete documentation index, see [llms.txt](https://max-daunarovich.gitbook.io/flow-network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://max-daunarovich.gitbook.io/flow-network/introduction/composite-types/resources/resource-variables.md).

# Resource Variables

Resource variables cannot be assigned to, as that would lead to the loss of the variable's current resource value.

Instead, use a swap statement (`<->`) or shift statement (`<- target <-`) to replace the resource variable with another resource.

```
pub resource R {}

var x <- create R()
var y <- create R()

// Invalid: Cannot assign to resource variable `x`,
// as its current resource would be lost
//
x <- y

// Instead, use a swap statement.
//
var replacement <- create R()
x <-> replacement
// `x` is the new resource.
// `replacement` is the old resource.

// Or use the shift statement (`<- target <-`)
// This statement moves the resource out of `x` and into `oldX`,
// and at the same time assigns `x` with the new value on the right-hand side.
let oldX <- x <- create R()
// oldX still needs to be explicitly handled after this statement
destroy oldX
```