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# affinity

Returns the selection affinity of the text selection.

```
var affinity: NSTextSelection.Affinity { get }
```

## Discussion

The affinity is [`NSTextSelection.Affinity.downstream`](/documentation/AppKit/NSTextSelection/Affinity-swift.enum/downstream) by default. For a zero-length selection, it describes the visual location of the text cursor between the head of line containing the selection location (downstream) or tail of the previous line (upstream). For a selection with contents, it describes the logical direction of non-anchored edge of the selection.

---

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