jorisvandenbossche commented on PR #14106: URL: https://github.com/apache/arrow/pull/14106#issuecomment-1259586863
> I think the main unresolved issue is whether we want to allow extension->extension casts: [#14106 (comment)](https://github.com/apache/arrow/pull/14106#discussion_r977663050) > > Personally, I think this would be useful, although I certainly agree that the cast will often not make much sense (depending on the extension type that is being used). But, I think that is just as true for any other cast to/from extension type in case it is not casting from/to the exact storage type (for example, we allow casting timestamp to int, but that doesn't mean that a cast from timestamp to extension-type-with-int-storage would make sense). Continuing on this myself: We could also restrict it (by default) to only casts from/to exactly the storage type? And allow the other casts behind a flag (like `allow_non_storage_extension_casts` ..., not sure I like that myself though) @pitrou you mentioned(https://github.com/apache/arrow/pull/14106#discussion_r977666643): > Being able to register extension-specific casts would be another separate possibility. In general that sounds interesting. Especially if that would also allow to change the behaviour of a specific cast (and not just allowing a pre-defined cast to/from the storage type). For example casting to string could give some actual string representation instead of just the string representation of the storage. But at the same time this also sounds quite complicated for a maybe limited use case? -- 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]
