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# mutableString

The character contents of the receiver as a mutable string object.

```
var mutableString: NSMutableString { get }
```

## Return Value

The mutable string object.

## Discussion

The receiver tracks changes to this string and keeps its attribute mappings up to date.

## See Also

  [Attributed String Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/AttributedStrings/AttributedStrings.html#//apple_ref/doc/uid/10000036i)


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