[Zope3-dev] Re: Proposed widget/schema work for the Rivah sprint (Thursday and Friday this week)

[Janko Hauser]

Am 07.09.2005 um 15:42 schrieb Tres Seaver:

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> Florent Guillaume wrote:
>
>> Jim Fulton wrote:
>>
>>
>>> I think that sources are different than initial value.  I really  
>>> don't
>>> see any role that "initial value" has in an object specification.
>>>
>>> A schema is a specification for an object that provides the schema.
>>> An initial value doesn't constrain or specify the object.  If  
>>> anything,
>>> it constrains applications that create the object, but in a rather
>>> unclear
>>> way.
>>>
>>
>>
>> But a schema is useful for more than "specifying the values of an
>> object". All notions of schemas I've encountered (CPS Schemas, XML
>> Schemas, Archetypes) use the schema to constrain or validate an  
>> existing
>> object, yes, but also to create new objects from scratch (even in the
>> absence of widgets). Being able to specify initial values is quite
>> important there.
>>
>
> RDBMS schemas are an important counter to the "default isn't schema"
> case, too.  Defaults become particularly important when migrating
> content "forward" over time.

But actually this started with the observation that if we keep  
default, we need something like a dynamic default, not only a fixed  
value in the schema definition. This happens for example if one wants  
to set the current date as the default.

Will this be adressed?

__Janko