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# CFStringAppend(_:_:)

Appends the characters of a string to those of a CFMutableString object.

```
func CFStringAppend(_ theString: CFMutableString!, _ appendedString: CFString!)
```

## Parameters

`theString`

The string to which `appendedString` is appended. If `theString` is not a CFMutableString object, an assertion is raised.

`appendedString`

The string to append.

## Discussion

This function reallocates the backing store of `theString` to accommodate the new length.

---

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