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# read(from:ofType:)

Sets the contents of this document by reading from a file wrapper of a specified type.

```
nonisolated func read(from fileWrapper: FileWrapper, ofType typeName: String) throws
```

## Parameters

`fileWrapper`

The file wrapper from which the document contents are read.

`typeName`

The string that identifies the document type.

## Discussion

The default implementation of this method invokes `[self readFromData:[fileWrapper regularFileContents] ofType:typeName error:outError]`.

For backward binary compatibility with OS X v10.3 and earlier, the default implementation of this method instead invokes `[self loadFileWrapperRepresentation:fileWrapper ofType:typeName]` if [`loadFileWrapperRepresentation:ofType:`](/documentation/AppKit/NSDocument/loadFileWrapperRepresentation:ofType:) is overridden.

> Handling Errors in Swift:
> In Swift, this method is marked with the `throws` keyword to indicate that it throws an error in cases of failure.
> 
> When overriding this method, use the `throw` statement to throw an `NSError`, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`.

---

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