[ZPT] Using variables in path expressions

[Brent M Hendricks]

On Sat, Jun 02, 2001 at 03:06:42PM -0500, Evan Simpson wrote:
> From: "Brent M Hendricks" <brent@valinor.waldenweb.com>
> > Is there a way to get variable substitutions in path expressions the
> > way we have them in string expressions?
> 
> > <div tal:repeat="item here/queryIds">
> >   <span tal:content="here/subfolder/${item/id}/method" />
> > </div>
> 
> 
> I admit that this is a little messy.  The undocumented capability does
> not allow paths (like 'item/id'), only raw variable names.  The name
> must contain either a string or a sequence of strings, which will be
> interpolated as one or more entire path segments:
> 
> tal:define="item_id item/id"
> tal:content="here/subfolder/?item_id/method"

Hmm.  Is there a technical reason why it uses a different syntax here?
In the interest of consistency, I'd think we would want to use ${} here
too.

And since I'm already nagging you about notation (<grin>), I might as
well ask: How hard would it be to allow paths embedded in paths?  I
would think you could just pass the expression through the "string:"
processor first to expand the variables and then pass the resultant
string into the "path:" processor.

Perhaps this is just my naive view of things and I should really just
shut up and dig into the code :)

--Brent


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