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# string(for:)

Formats `obj` as a byte count (if `obj` is an `NSNumber`) or specific byte measurement (if `obj` is an `NSMeasurement`) using the receiver’s settings.

```
func string(for obj: Any?) -> String?
```

## Discussion

Returns `nil` if `obj` is not of the correct class (`NSNumber` or `NSMeasurement`).
Throws an exception if `obj` is an `NSMeasurement` whose unit does not belong to the `NSUnitInformationStorage` dimension.

---

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