[Zope3-dev] Re: [z3-five] zcml questions

[Jim Fulton]

On Sep 21, 2006, at 9:15 AM, Tres Seaver wrote:
>
> I've wanted it.  My major beef with the way we are *using* ZCML now is
> that we expect package authors to provide policy-laden  
> configuration for
> their packages ("sensible defaults") but provide no means for the  
> admin
> to reuse that configuration selectively;  their only realy choice  
> is to
> *copy* the configuration and edit it.

This is mostly true.  I'll note that it is straightforward to  
override things.  It isn't straightforward to disable things,  
especially subscribers.

Anyway, I think you raise a good point.

> I argued *long* ago (after the first ZC-internal Zope3 sprint, I  
> think)
> that the '<include>' directive should be allowed to be complex, with
> subelements like '<except>' or '<only>' to pull in specific  
> directives.
>  Such a practice would require either that we have XPath support
> available, or else that we come up with a way to mark the directives
> (e.g., a 'zcml:id' attribute).

I don't remember this, but I may have been focussed on other things.  
I definitely think it would be good to have something like this.  It  
would be interesting to see some proposals with examples.

>   It would *also* require that we
> implement the "no side-effects during parsing" policy (my other  
> favorite
> "dead horse" in arguments about ZCML's implementation / usage).

Beat away. :)  I've been in favor of this for some time.  This is  
definitely a goal.

Jim

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