---
title: SecTransformMetaAttributeType.ref
framework: security
role: symbol
role_heading: Case
path: security/sectransformmetaattributetype/ref
---

# SecTransformMetaAttributeType.ref

A direct reference to an attribute’s value.

## Declaration

```swift
case ref
```

## Discussion

Discussion This reference allows for direct access to an attribute without having to look up the attribute by name. If a transform commonly uses an attribute, using a reference speeds up the use of that attribute. Attribute references are not visible or valid from outside of the particular transform instance.