While looking at the Plone versioning code the other day, it struck me that it would be much more efficient to implement file versioning if we could rely on blobs never changing after their first commit, as a copy of the file data would not need to be made proactively in the versioning repository incase the blob was changed in a future transaction.
Subclassing of blobs is not supported, but looking at the code I didn't see anything that actively prevented this other than the Blob.__init__ itself. Is there something I've missed here? I had thought that an ImmutableBlob could be implemented by overriding the open and consumeFile methods of Blob to prevent modification after first commit. Laurence _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev