---
title: "extracting(_:)"
framework: swift
role: symbol
role_heading: Instance Method
path: "swift/unsafebufferpointer/extracting(_:)-nivx"
---

# extracting(_:)

Constructs a standalone buffer pointer over the items within the supplied range of positions in the memory region addressed by this buffer pointer.

## Declaration

```swift
func extracting(_ bounds: Range<Int>) -> UnsafeBufferPointer<Element>
```

## Parameters

- `bounds`: A valid range of indices within this buffer.

## Return Value

Return Value A new buffer pointer over the items at bounds.

## Discussion

Discussion The returned buffer’s first item is always at index 0; unlike buffer slices, extracted buffers do not generally share their indices with the original buffer pointer. withUnsafeTemporaryAllocation(of: Int.self, capacity: 5) { buffer in   buffer.initialize(repeating: 0)   // buffer contains [0, 0, 0, 0, 0]   let part = buffer.extracting(2 ..< 4)   part[0] = 1   part[1] = 2   // buffer now contains [0, 0, 1, 2, 0] } When Element is copyable, the extracting operation is equivalent to slicing the buffer then rebasing the resulting buffer slice: let a = buffer.extracting(i ..< j) let b = UnsafeBufferPointer(rebasing: buffer[i ..< j]) // `a` and `b` are now holding the same buffer However, unlike slicing, the extracting operation remains available even if Element happens to be noncopyable.