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# NSLayoutConstraint.Attribute.notAnAttribute

A placeholder value for indicating that the constraint’s second item and second attribute aren’t used in any calculations.

```
case notAnAttribute
```

## Discussion

Use this value when creating a constraint that assigns a constant to an attribute. For example, `item1.height >= 40`. If a constraint only has one item, set the second item to `nil`, and set the second attribute to [`NSLayoutConstraint.Attribute.notAnAttribute`](/documentation/AppKit/NSLayoutConstraint/Attribute/notAnAttribute).

---

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