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# shift(startingAt:by:)

For a positive delta, shifts the indexes in [index, INT_MAX] to the right, thereby inserting an “empty space” [index, delta], for a negative delta, shifts the indexes in [index, INT_MAX] to the left, thereby deleting the indexes in the range [index - delta, delta].

```
mutating func shift(startingAt integer: IndexSet.Element, by delta: Int)
```

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