UserDict -> dict, reasons for migrating existing code

[Andreas Kuntzagk]

Hi,

what would be the reasons to migrate existing code from the use of
UserDict() to dict()? (UserString ...) What would be reasons against?
Reasons I can think of:
pro:
- Speed Improvement because of a level of indirection less
- UserDict can become deprecated

con:
- Code not working whith older python
- cost of migrating large codebase

Do you know other reasons?

Andreas

 

[Steven Taschuk]

Quoth Andreas Kuntzagk:
[...]

what would be the reasons to migrate existing code from the use of
UserDict() to dict()? (UserString ...) What would be reasons against?
Reasons I can think of:
pro:
- Speed Improvement because of a level of indirection less
- UserDict can become deprecated

con:
- Code not working whith older python
- cost of migrating large codebase

Do you know other reasons?

I think there are still some issues with subclassing the built-in
types, but I've no idea what they are. (Hopefully somebody more
knowledgeable will comment.)

Your thought that a dict subclass might be faster than a UserDict
subclass is plausible, but I'd strongly suggest doing some timing
experiments before doing any large migration under that assumption.

Otherwise, I think you've said everything.