AW: AW: [Zope3-dev] Re: AW: Re: edit view of a object unknown?

[Jim Fulton]

Roger ineichen wrote:
>>Jim Fulton wrote:
>>I will note that Object field provide much more freedom than 
>>other fields. Most other fields imply a specific 
>>implementation type.  For example, Int implies int and Text 
>>implies unicode.
>>
>>Squence and Object let you provide any objects that satisfy a 
>>contract and are less help when constructing things. Or they 
>>are more help, because they are more flexible. With freedom 
>>comes responsibility. There are tradeoffs involved.
>>
>>We may find that people end up providing concrete classes for 
>>object felds instead of interfaces. I'd be open to allowing 
>>this. An object field that specifies a class is more like a 
>>Int or Text field.  It is easier to work with but less 
>>flexible.  Most applications won't really need the 
>>flexibility of allowing multiple implementations.
> 
> 
> Let's try to solve this restriction.

What restriction.

> I think, we don't have enough information just in the 
> interface.

Interfaces constrain implementations. They don't determine
implementations. This is intentional.  This is intentional.

 > We need sometimes more nformation, for get
> the felxibility back, form the configuration on the server.
> 
> If we whould provide a registration directive for to 
> tell which Object is used in a class(interface). 
> We could use this registred Objects.
> 
> Important,
> This is not just a problem of the Object(field).
> Allways if you call a registred component of a given 
> Interface you can get back more then one components.
> This is hadled in different ways. 
> e.g. in menu service give back the first menu item (I think) 
> and in workflow.ImportExportUtility give back the first
> ProcessDefinition.
> Here it whold be nice to give back what's registred in
> ZCML.
> 
> Sorry it's really hard for me to tell this in english.
> I hoppe you understand this above.

I can't tell if I don't understand, or if I simply don't agree.

Your arguments are far too general to be convincing to me.

> See more information on the tread "edit view of a object unknown"
> with Jim and Garrett

I read and responded to that thread. In fact, that's the thread we're on
now.

Jim

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