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# utf8Span

A UTF-8 span over the code units that make up this string.

```
var utf8Span: UTF8Span { get }
```

## Return Value

A `UTF8Span` over the code units of this `String`.

## Discussion> Note: On Apple platforms, this property transcodes the code units
> of bridged UTF-16 `String` instances on first access and caches
> the result. Subsequent calls can reuse the cached buffer.

> Complexity: O(1) for native UTF-8 strings, amortized O(1) for bridged
> UTF-16 strings.

---

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