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# NSUnionRect(_:_:)

Calculates the union of two rectangles.

```
func NSUnionRect(_ aRect: NSRect, _ bRect: NSRect) -> NSRect
```

## Discussion

Returns the smallest rectangle that completely encloses both `aRect` and `bRect`. If one of the rectangles has 0 (or negative) width or height, a copy of the other rectangle is returned; but if both have 0 (or negative) width or height, the returned rectangle has its origin at (0.0, 0.0) and has 0 width and height.

---

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