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# PreviewTimelineBuilder

```
@resultBuilder struct PreviewTimelineBuilder
```

## Topics

### Previewing timelines

[`static func buildArray([[any TimelineEntry]]) -> [any TimelineEntry]`](/documentation/WidgetKit/PreviewTimelineBuilder/buildArray(_:))

[`static func buildExpression(some TimelineEntry) -> [any TimelineEntry]`](/documentation/WidgetKit/PreviewTimelineBuilder/buildExpression(_:))

[`static func buildPartialBlock(accumulated: [any TimelineEntry], next: [any TimelineEntry]) -> [any TimelineEntry]`](/documentation/WidgetKit/PreviewTimelineBuilder/buildPartialBlock(accumulated:next:))

[`static func buildPartialBlock(first: [any TimelineEntry]) -> [any TimelineEntry]`](/documentation/WidgetKit/PreviewTimelineBuilder/buildPartialBlock(first:))


---

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