---
title: base
framework: Assignables
role: symbol
role_heading: Type Property
platforms: [iOS 17.4+, iPadOS 17.4+, Mac Catalyst 17.4+]
path: assignables/assignabledocument/partids-swift.enum/base
---

# base

The identifier for the part that contains the base PDF upon which this document is built.

## Declaration

```swift
static let base: MergeablePartsContainerPartID
```

## See Also

### Layer types

- [all](assignables/assignabledocument/partids-swift.enum/all.md)
- [authors](assignables/assignabledocument/partids-swift.enum/authors.md)
- [instructionMarkup](assignables/assignabledocument/partids-swift.enum/instructionmarkup.md)
- [questionBoxes](assignables/assignabledocument/partids-swift.enum/questionboxes.md)