 		}
 	}
 
-	private func _copyBytesHelper(to pointer: UnsafeMutableRawPointer, from range: CountableRange<Index>) {
+	private func _copyBytesHelper(to pointer: UnsafeMutableRawPointer, from range: Range<Index>) {
 		var copiedCount = 0
 		if range.isEmpty { return }
 		let rangeSize = range.count

	/// - 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)

public struct DispatchData : RandomAccessCollection {
	public typealias Iterator = DispatchDataIterator
	public typealias Index = Int
	public typealias Indices = DefaultIndices<DispatchData>

	public static let empty: DispatchData = DispatchData(data: _swift_dispatch_data_empty())

