 	/// - parameter pointer: A pointer to the buffer you wish to copy the bytes into.
 	/// - parameter range: The range in the `Data` to copy.
 	/// - warning: This method does not verify that the contents at pointer have enough space to hold the required number of bytes.
-	@available(swift, deprecated: 4, message: "Use copyBytes(to: UnsafeMutableRawBufferPointer, from: CountableRange<Index>) instead")
-	public func copyBytes(to pointer: UnsafeMutablePointer<UInt8>, from range: CountableRange<Index>) {
+	@available(swift, deprecated: 4, message: "Use copyBytes(to: UnsafeMutableRawBufferPointer, from: Range<Index>) instead")
+	public func copyBytes(to pointer: UnsafeMutablePointer<UInt8>, from range: Range<Index>) {
 		_copyBytesHelper(to: pointer, from: range)
 	}
 	

	/// - parameter pointer: A pointer to the buffer you wish to copy the bytes into. The buffer must be large
	///	enough to hold `count` bytes.
	/// - parameter range: The range in the `Data` to copy.
	public func copyBytes(to pointer: UnsafeMutableRawBufferPointer, from range: CountableRange<Index>) {
		assert(range.count <= pointer.count, "Buffer too small to copy \(range.count) bytes")
		guard pointer.baseAddress != nil else { return }
		_copyBytesHelper(to: pointer.baseAddress!, from: range)


	/// Advance to the next element and return it, or `nil` if no next
	/// element exists.
	public mutating func next() -> DispatchData.Element? {
		if _position == _count { return nil }
		let element = _ptr.load(fromByteOffset: _position, as: UInt8.self)
		_position = _position + 1
