jorisvandenbossche commented on issue #39094:
URL: https://github.com/apache/arrow/issues/39094#issuecomment-1845614035

   Quickly looking into this, but now I am unsure whether it's actually an easy 
change as I mentioned at 
https://github.com/apache/arrow/pull/35933#issuecomment-1841288493 to use 
`self.ext_type.Deserialize(..)`. 
   
   To be able to call the C++ `Deserialize` method, we first need to 
instantiate the relevant C++ ExtensionType in the cython unpickle method. But 
how do you do that? When you have a python instance, you can get that with 
`self.ext_type`. But when unpickling, you don't have an instance of the 
specific extension type class yet, because that's exactly what you are 
unpickling.
   
   For pyarrow.ExtensionType, `__arrow_ext_deserialize__` is also a classmethod 
(i.e. doesn't require an instance), but the implementation here is in python 
and custom done by the user and can call the class constructor of itself as it 
sees fit. However, if we want to put similar generic logic on the 
BaseExtensionType class, there is no `__init__` that we can call.
   
   But maybe I am overlooking something cc @pitrou 


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to