 
   /// Destroy the stored Header.
   deinit {
-    ManagedBufferPointer(self).withUnsafeMutablePointerToHeader { $0.deinitialize() }
+    ManagedBufferPointer(self).withUnsafeMutablePointerToHeader {
+      $0.deinitialize()
+    }
   }
 
   /// The stored `Header` instance.
   public final var header: Header {
     addressWithNativeOwner {
       return (
-        ManagedBufferPointer(self).withUnsafeMutablePointerToHeader { UnsafePointer($0) },
+        ManagedBufferPointer(self).withUnsafeMutablePointerToHeader {
+          UnsafePointer($0)
+        },
         Builtin.castToNativeObject(self))
     }
     mutableAddressWithNativeOwner {

  : ManagedProtoBuffer<Header, Element> {

  /// Create a new instance of the most-derived class, calling
  /// `initialHeader` on the partially-constructed object to
  /// generate an initial `Header`.
  public final class func create(
    minimumCapacity: Int,
    initialHeader: @noescape (ManagedProtoBuffer<Header, Element>) throws -> Header
  ) rethrows -> ManagedBuffer<Header, Element> {

    let p = try ManagedBufferPointer<Header, Element>(
      bufferClass: self,
      minimumCapacity: minimumCapacity,
      initialHeader: { buffer, _ in
        try initialHeader(
          unsafeDowncast(buffer, to: ManagedProtoBuffer<Header, Element>.self))
      })


  public init(
    bufferClass: AnyClass,
    minimumCapacity: Int,
    makingHeaderWith factory:
      (buffer: AnyObject, capacity: (AnyObject) -> Int) throws -> Header
  ) rethrows {
    self = ManagedBufferPointer(
      bufferClass: bufferClass, minimumCapacity: minimumCapacity)

    // initialize the header field
    try withUnsafeMutablePointerToHeader {
      $0.initialize(with: 
        try factory(
          buffer: self.buffer,
          capacity: {
            ManagedBufferPointer(unsafeBufferObject: $0).capacity
