Rocky has a narrow classification of subtyping: allowing subclassification of an existing content type. An advantage is a delayed specification: you don't need to know exactly what you want to do with a more generic type ("I'm going to handle files, but I might want to do special things with them.")
You could for example let a content type have a different identity based on
the situation. An
*.ogg file could be just audio, but also video+audio. He's
p4a.subtyper, a minimal framework for dealing with this. It hooks up
subtypes into the content menu (in a special "sub-types" menu next to the
"actions" and "state" menu). A simple demo is at
p4a.subtyper allows you to specify an interface for the new subtype and hook it up with a custom view. There's a special ISubtypeAdded/ISubtypeRemoved event that is fired when you (description by Reinout:) "tag a basic type with a subtype".
Extra info at serverzen.com .
Technorati tag: ploneconf2007
My name is Reinout van Rees and I work a lot with Python (programming language) and Django (website framework). I live in The Netherlands and I'm happily married to Annie van Rees-Kooiman.
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