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# CFAttributedStringSetAttributes(_:_:_:_:)

Sets the value of attributes of a mutable attributed string over a specified range.

```
func CFAttributedStringSetAttributes(_ aStr: CFMutableAttributedString!, _ range: CFRange, _ replacement: CFDictionary!, _ clearOtherAttributes: Bool)
```

## Parameters

`aStr`

The mutable attributed string to modify.

`range`

The range of aStr over to which the new attributes apply. `range` must not exceed the bounds of `aStr`.

`replacement`

A dictionary that contains key-value pairs that specify the new attributes to apply to `range`. The keys must be CFString objects, and the corresponding values must be CFType objects.

`clearOtherAttributes`

If `false`, existing attributes (that aren’t being replaced) are left alone; otherwise they are cleared.

## Discussion

Note that after this call, if it is mutable, changes to `replacement` will not affect the contents of the attributed string.

---

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