# Reference

# Reference


```
class Reference : Expression
```

<br />

*** ** * ** ***

Represents a reference to a previously defined node in the automation graph, or an list element for list comprehension expression .

## Summary

| ### Public constructors |
|---|
| `https://developers.home.google.com/reference/kotlin/com/google/home/automation/Reference#Reference(com.google.home.automation.ReferenceDeclaration)(referenceDeclaration: https://developers.home.google.com/reference/kotlin/com/google/home/automation/ReferenceDeclaration)` Create a `Reference` instance from a `https://developers.home.google.com/reference/kotlin/com/google/home/automation/ReferenceDeclaration`. |
| `https://developers.home.google.com/reference/kotlin/com/google/home/automation/Reference#Reference(com.google.home.automation.HasOutput)(reference: https://developers.home.google.com/reference/kotlin/com/google/home/automation/HasOutput)` Create a `Reference` instance. |

| ### Public properties |
|---|---|
| `https://developers.home.google.com/reference/kotlin/com/google/home/automation/HasOutput?` | `https://developers.home.google.com/reference/kotlin/com/google/home/automation/Reference#reference()` |
| `https://developers.home.google.com/reference/kotlin/com/google/home/automation/ReferenceDeclaration?` | `https://developers.home.google.com/reference/kotlin/com/google/home/automation/Reference#referenceDeclaration()` |

## Public constructors

### Reference

```
Reference(referenceDeclaration: ReferenceDeclaration)
```

Create a `Reference` instance from a `https://developers.home.google.com/reference/kotlin/com/google/home/automation/ReferenceDeclaration`.

### Reference

```
Reference(reference: HasOutput)
```

Create a `Reference` instance.

| Parameters |
|---|---|
| `reference: https://developers.home.google.com/reference/kotlin/com/google/home/automation/HasOutput` | The reference. |

## Public properties

### reference

```
val reference: HasOutput?
```

### referenceDeclaration

```
val referenceDeclaration: ReferenceDeclaration?
```