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# callAsFunction(_:)

Builds an attribute container by setting an attribute and returning a modified attribute container.

```
@preconcurrency func callAsFunction(_ value: T.Value) -> AttributeContainer where T.Value : Sendable
```

## Parameters

`value`

The value to set on the returned attribute container.

## Return Value

An attribute container with the provided value set on the builder’s [`AttributedStringKey`](/documentation/Foundation/AttributedStringKey).

---

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