[Zope-CMF] Re: ICMFTool marker interface
Philipp von Weitershausen
philipp at weitershausen.de
Mon Apr 19 12:25:28 EDT 2004
Christian Heimes wrote:
> I would like to add a marker interface for CMF tools to CMFCore,
> CMFDefault, CMFActionIcons and EventListenerTool.
This proposal lacks a problem description and a detailled discussion of
why you think this would fix the problem, including practical use-cases.
Anyway, considering the idea itself, I would suggest adopting a pattern
we're using in Zope3. Instead of deriving IActionIcons from ICMFTool and
thus requiring every CMF tool to implement ICMFTool, directly or
indirectly, I would suggest the following setup::
from Interface.IInterface import IInterface
# note that we derive from *I*Interface
"""Meta-interface that is implemented by interfaces that
describe CMF Tools."""
Then, the interface for a tool, such as CMFActionIcons tool would look
from Interface import Interface
"""Interface for a tool providing icons for actions."""
# IActionIconsTool is an interface describing a CMF Tool
from Interface.Implements import implements
A simple algorithm (that would need to be adapted to old-style
interfaces) can be found at:
(search for queryType).
Likewise, one could start having content interfaces implement
IContentType, also a marker interface derived from IInterface. We
already do that in Zope3 and it would make transition even smoother.
Then again, frameworks like Archetype completely ignore interfaces and
rather use their own descriptors. A shame.
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