Re: [Avalon4:PROPOSAL] Context Consensus (version 2)

Paul Hammant wrote:

> Stephen, Leo,
>
>> [...] A Context contract is
>>   defined by (1) an optional target class,
>> [...]
>>      A container shall ensure that a context object supplied
>>      to a component shall be castable to a target class or
>>      interface (T).  The default target class is Context. A
>>      target class must be derived from or implement the
>>      Context interface. 
>
>
> I'm unhappy with anything other than a base interface (Context) or 
> specialised interfaces (e.g. BlockContext) being used to descibe 
> parameter0 of contextualize for the IS-A proposition.  Why? K/HC/CAPI 
> separation; separation of interface and impl etc.  As an advocate of 
> the BlockContext (and alike) solution I have no requirement for things 
> like GenericBlockContext (it was a class not an interface).


I agree - it was something that was bugging me about the summary.  I 
would prefer that the value of "type" on a <context> element be 
restricted to an interface derived from Context.  Things like 
"GenericBlockContext" could appear as part of a creation directive 
(meta-data), but that has nothing to do with the context criteria 
expressed by a component towards the container and is not relevant to 
the Context interface specification.

Cheers, Steve.

-- 

Stephen J. McConnell

OSM SARL
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