Update documentation for PointerHolder transition

1 files changed, 9 insertions, 4 deletions

diff --git a/README-maintainer b/README-maintainer
index 9f597d35..60e7de57 100644
--- a/README-maintainer
+++ b/README-maintainer
@@ -160,11 +160,16 @@ CODING RULES
   it seems also for classes that are intended to be subclassed across
   the shared library boundary.
 
-* Put private member variables in PointerHolder<Members> for all
+* Put private member variables in std::shared_ptr<Members> for all
   public classes. Remember to use QPDF_DLL on ~Members(). Exception:
-  indirection through PointerHolder<Members> is expensive, so don't do
-  it for classes that are copied a lot, like QPDFObjectHandle and
-  QPDFObject.
+  indirection through std::shared_ptr<Members> is expensive, so don't
+  do it for classes that are copied a lot, like QPDFObjectHandle and
+  QPDFObject. It may be possible to declare
+  std::shared_ptr<Members> m_ph;
+  Member* m;
+  with m = m_ph.get(), and then indirect through m in
+  performance-critical settings, though in 2022, std::shared_ptr is
+  sufficiently performant that this may not be worth it.
 
 * Traversal of objects is expensive. It's worth adding some complexity
   to avoid needless traversals of objects.