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# init(buffer:initializedCount:)

Unsafely create an OutputRawSpan over partly-initialized memory.

```
init(buffer: UnsafeMutableRawBufferPointer, initializedCount: Int)
```

## Parameters

`buffer`

an `UnsafeMutableRawBufferPointer` to be initialized

`initializedCount`

the number of initialized bytes
at the beginning of `buffer`.

## Discussion

The memory in `buffer` must remain valid throughout the lifetime
of the newly-created `OutputRawSpan`. Its prefix must contain
`initializedCount` initialized bytes, followed by uninitialized
memory.

---

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