PEP 249 refers to StandardError (gone in Python 3)

[pchemguy]

PEP 249 / DB API 2.0 refers to the StandardError Python exception as the starting point for its exception hierarchy, but this exception is gone in Python 3.

[Rosuav]

Should the document say "must be a subclass of Exception" or just drop that requirement altogether?

[CAM-Gerlach]

Normally, PEPs are considered historical documents, but in this special case it describes an ongoing specification, and I'm not sure there is another place this is documented (though perhaps ideally there should be). Pinging @malemburg as the PEP author and @erlend-aasland as a core dev whom I know is active with DB-API stuff to take a look at this.

[malemburg]

On 28.08.2022 18:52, C.A.M. Gerlach wrote: Normally, PEPs are considered historical documents, but in this special case it describes an ongoing specification, and I'm not sure there is another place this is documented (though perhaps ideally there should be). Pinging @malemburg <https://github.com/malemburg> as the PEP author and @erlend-aasland <https://github.com/erlend-aasland> as a core dev whom I know is active with DB-API stuff to take a look at this.

PEP 249 is an informational PEP and the documentation of a living standard in Python. The DB-SIG still makes changes to the PEP every now and then. It is interesting that this difference between Python 2 and 3 wasn't raised earlier. I could also not find any documentation on why StandardError was removed in Python 3. There's no PEP or other documentation explaining the reasoning. The only document mentioning the removal is the "What's New in Python 3.0" (https://docs.python.org/3.7/whatsnew/3.0.html). In any case, the correct replacement in Python 3 is "Exception" and I'll add a note to the PEP.

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-- Marc-Andre Lemburg http://www.malemburg.com/

[Rosuav]

The justification for removing StandardError was basically "it ain't needed no more". From my reading of things, it looks like the removal of string exceptions also removed the need for extra types of hierarchy in class exceptions.

I think the entire sentence can be dropped, actually - if it weren't there, anyone creating a database module would still use Exception as a base class, as subclassing BaseException directly is rare and not what you'd want here.