[PEAK] Overriding getter/setter of a model

[Phillip J. Eby]

At 03:02 PM 7/27/2005 +0000, Tiago Cogumbreiro wrote:
>Lo list,
>
>Is there any way to override the setter/getter of a model's field?

If all you want is to be notified of a change, you should define _onLink 
and _onUnlink methods in the attribute class body.

If you want to override the getter to create a computed or derived field, 
you should set 'isDerived = True' and then define a 'get(feature,element)' 
method; see peak.model.features starting at line 292 for examples of 'get' 
methods.

By default, derived fields are not changeable, unless you also define a 
set(feature,element,value) method, and explicitly set isChangeable to True.