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# extracting(droppingFirst:)

Returns a span over all but the given number of initial bytes.

```
mutating func extracting(droppingFirst k: Int) -> MutableRawSpan
```

## Parameters

`k`

The number of bytes to drop from the beginning of
the span. `k` must be greater than or equal to zero.

## Return Value

A span starting after the specified number of bytes.

## Discussion

If the number of bytes to drop exceeds the number of bytes in
the span, the result is an empty span.

The returned span represents a mutation of this span.

The returned span’s first item is always at offset 0; unlike buffer
slices, extracted spans do not share their indices with the
span from which they are extracted.

> Complexity: O(1)

---

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