thinking over the last posts and the usage of actions in zope.formlib
in general, I would say:
We should search for a better way how to implement actions in formlib.
If you want to subclass an existing form class and change any
behavior in an action handler method, you have to redelcare the
action completely, including translation of the action title, the
condition and eventually a validator. I think this is too much
duplication because most of these redeclared parameters are only copy-
paste (+ imports!) from the super class.
But I have no clever solution for this. My suggestion from the
initial post (make usage of function applyChanges compatible with
subclassing) is not a good solution because according to Fred Drake
the validator should compute the normalized values, so changing
things in applyChanges is too late. And my suggestion does not allow
to use different normalizations for different actions in the same class.
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