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# reset(toUnchecked:)

Reset this iterator to `codeUnitOffset`, skipping *all* safety
checks (including bounds checks).

```
mutating func reset(toUnchecked codeUnitOffset: Int)
```

## Discussion

Note: This is only for very specific, low-level use cases. If
`codeUnitOffset` is not properly scalar-aligned, this function can
result in undefined behavior when, e.g., `next()` is called.

For example, this could be used by a regex engine to backtrack to a
known-valid previous position.

> Complexity: O(1)

---

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