[Zope] (sort of teaser) Re: [Zope] Recursive aquisition: good or bad?

[Michel Pelletier]

> -----Original Message-----
> From: Anthony Baxter [mailto:anthony@interlink.com.au]
> Sent: Tuesday, June 08, 1999 5:57 AM
> To: Tom Schwaller
> Cc: zope@zope.org
> Subject: [Zope] (sort of teaser) Re: [Zope] Recursive aquisition: good
> or bad?
> 
> In more detail, the problem I have is that in the 
> bobo_traverse method, if
> I get a constraint, I want to store this. The way I do this 
> is to instantiate
> a new DMC - but one that's non-persistant, populate it, then 
> return it.
> Unfortunately to get it to acquire everything else it needs, 
> I need to 
> attach it to the 'self' object with something like 
> 
>   self.new = DMC_nonP(self.id, self.name, ....)
>   ... set the magic in the new object ...
>   return self.new
> 
> Unfortunately this self.new assignment makes an entry in the 
> ZODB. Blah.
> 

You could call it self._v_new and the persistence machinery will never
store it in the database.  Attributes starting with _v_ are 'volitile'.

Do you want your new DMC_nonP objects to acquire from 'self' as their
parent?  You can do this without an assignment (I think this is right,
never atctually put it to the test):

	x = DMC(...)
	return x.__of__(self)

x must inherit ExtensionClass.Base to get this machinery.  This returns
an Acquisition wrapped object whose ac_parent is 'self'.

-Michel the Acquired

inherit at least ExtensionClass.Base to do this.

> Anyway, I plan to fling a release of some sort out tonight, bug or no
> bug.
> 
> Anthony
> 
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