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# nextDown

The greatest representable value that compares less than this value.

```
var nextDown: Self { get }
```

## Discussion

For any finite value `x`, `x.nextDown` is less than `x`. For `nan` or
`-infinity`, `x.nextDown` is `x` itself. The following special cases
also apply:

- If `x` is `infinity`, then `x.nextDown` is `greatestFiniteMagnitude`.
- If `x` is `leastNonzeroMagnitude`, then `x.nextDown` is `0.0`.
- If `x` is zero, then `x.nextDown` is `-leastNonzeroMagnitude`.
- If `x` is `-greatestFiniteMagnitude`, then `x.nextDown` is `-infinity`.

---

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