[Zope] Namespace + syntax question

[Tres Seaver]

Evan Simpson wrote:
> 
> ----- Original Message -----
> From: Tres Seaver <tseaver@palladion.com>
> > I usually end up throwing in a '<dtml-let ...>' to alias those ridiculous
> > "identifiers".  What is the status of the patch to alias them
> automatically (I
> > _still_ can't figure out why they exist)?
> 
> One thing I find myself often wanting is the ability to do this:
> 
> <dtml-in expr="arg.bargle[mumble](frotz)" sequence-var=fred>
>   <dtml-in expr="fred.item(3)">
>     <dtml-var fred/index>: <dtml-var fred/key> <dtml-var sequence-item>
>   </dtml-in>
> </dtml-in>

'<dtml-var fred/index>'??? Are you using some bleading-edge CVS checkout that
makes the "/" work like that?  Anyway, I think the notion of a "brains"/iterator
object makes sense. It would have the properties:

   name=        expr=          Semantics
   =========    ===========    ================================================

 - fred-item    fred.item      "Unwrap" the object, like 'sequence-item'

 - fred-index   fred.index     Like 'sequence-index'

 - fred-isStart fred.isStart   Like 'sequence-start' (renamed to show predicate)

 - fred-isEnd   fred.isEnd     Like 'sequence-end' (renamed to show predicate)

and any of the others in the current "sequence-blah" set.  The
'sequence-var-nnn' bit could be handled
through pure dictionary-style lookup (fred[ 'nnn' ]), or through mangling the
identifier (fred-var-nnn).  The mapping keyword would set a flag on fred which
caused any non-standard getattr to delegate to the wrapped item (or is that
getitem?).  We could even call the default brains object "sequence", to maintain
backward compatibility.

> 
> ...instead of...
> 
> <dtml-in expr="arg.bargle[mumble](frotz)">
>   <dtml-let fred_index=sequence-index fred_item=sequence-item
> fred_key=sequence-key>
>   <dtml-in expr="fred_item(3)">
>     <dtml-var fred_index>: <dtml-var fred_key> <dtml-var sequence-item>
>   </dtml-in>
>   </dtml-let>
> </dtml-in>
> 
> What do you think?
> 
> Cheers,
> 
> Evan @ digicool


-- 
=========================================================
Tres Seaver         tseaver@palladion.com    713-523-6582
Palladion Software  http://www.palladion.com