[ZPT] Re: DTML/ZPT examples

[Brent M Hendricks]

Hi Peter,

I was looking over your DTML to ZPT example page (great job by the
way!).  I think there is a better way to approach example 2:condition
testing.

Currently you have:

<H4>
<span tal:replace="template/title" 
        tal:condition="python:len(result)==0"/>
<span tal:replace="string:Untitled"
        tal:condition="python:not(len(result)==0)"/>
</H4>

which works, but requires the use of an extra span tag.  I would like
to propose the following alternative:

<H4 tal:content="python:test(len(result)==0, path('template/title'), 'Untitled')">Dummy Title</H4>

which achieves the same effect.

Keep up the good work!

--Brent

On Mon, May 28, 2001 at 10:06:10AM +0200, Peter Bengtsson wrote:
> Content changed. (2001-05-28 03:57)
> 
> Cool!
> That's great. I was hoping that the community could help me with that page.
> If you want to add anything new, I'll add it without doubt, now that you
> have proved skilled enough :)
> 
> perhaps you can translate this one for me?
> 
> DTML:
> <dtml-with subfolder>
>   <dtml-if anotherpageobject>
>     <tr>
>         <td><dtml-var "anotherpageobject.title"></td>
>         <td><a href="<dtml-var "anotherpageobject.absolute_url()">"
> title="<dtml-var "anotherpageobject.title">"><dtml-var
> "anotherpageobject.title"></td>
>     </tr>
>   </dtml-if>
> </dtml-with>
> 
> 'anotherpagepobject' might not even exist. I.e. not created yet.
> The ZPT must skip the whole <TR> tag if the object doesn't exist.
> 
> Can we have some support from the rest of the ZPT mailing list on how to use
> the latest spec and the flashy path things et al that DC have recently
> released?
> 
> Cheers, Peter
> 
> PS. Andreas, CC in the zpt so when can all enjoy your replies.
> 
> ----- Original Message -----
> From: "Andreas Vallen" <vallen@gmx.net>
> To: "Peter Bengtsson" <mail@peterbe.com>
> Sent: Friday, May 25, 2001 6:42 PM
> Subject: Re: DTML/ZPT examples
> 
> 
> > Hi Peter,
> >
> > I`ve just taken the time to check out your changed ZPT/DTML
> > example code #2.
> > Amazing how something seemingly this simple makes me become confused.
> > I think we still haven't got it right though.
> >
> > you wrote:
> > "Both BL will print the <H4> tags independent of what happens."
> >
> > Unfortunately this seems not to happen:
> > "tal:condition" makes the whole tag disappear if it is not met.
> > Even in conjunction with "tal:content"
> >
> > So:
> > <H4 tal:content="template/title"
> >     tal:condition="python:0">
> >   Untitled</H4>
> >
> > will render as nothing (""). Not even the H4-Tag will show up.
> >
> > I make the following proposal:
> >
> > DTML:
> > <dtml-if "_.len(result)==0">
> >   <H4><dtml-var document_title></H4>
> > </dtml-if>
> >
> > <H4 tal:content="template/title"
> >     tal:condition="python:len(result)==0">
> > </H4>
> >
> >
> > If no title exists nothing will get rendered.
> > To render "untitled" in this case one could use your
> > current DTML-example:
> >
> > <H4>
> > <dtml-if "_.len(result)==0">
> >   <dtml-var document_title>
> > <dtml-else>
> >   Untitled
> > </dtml-if>
> > </H4>
> >
> > and the following ZPT:
> >
> > <H4>
> >   <span tal:replace="template/title"
> >         tal:condition="python:len(result)==0"/>
> >   <span tal:replace="string:Untitled"
> >         tal:condition="python:not(len(result)==0)"/>
> > </H4>
> >
> > I think this is necessary - we don't have "else" in
> > ZPT, so we use "tal:condition" with the inverse expression.
> >
> > Your page is a good help for anyone starting to grasp ZPT.
> > Good work. Especially regarding the shortage of documentation
> > of our supposed new Templating mechanism of choice.
> >
> > Ciao, Andreas
> >
> >
> >
> > Montag, 21. Mai 2001 10:50 you wrote:
> > > Cheers!
> > >
> > > <H4>
> > > <dtml-if "_.len(result)==0">
> > >   <dtml-var document_title>
> > > <dtml-else>
> > >   Untitled
> > > </dtml-if>
> > > </H4>
> > >
> > > |-split-|
> > >
> > > <H4 tal:content="template/title"
> > >     tal:condition="python:len(result)==0">
> > >   Untitled</H4>
> > >
> > >
> > >
> > > Better?
> > >
> http://www.zope.org/Members/peterbe/DTML2ZPT_Conversion_examples/#example2
> > >
> > > Is this right?
> > > Both BL will print the <H4> tags independent of what happens.
> > > If the python:len(result) condition is met, the tal:replace occurs. If
> the
> > > condition thing "fails", it leaves the ZPT alone on that tag.
> > >
> > > Swedish?
> > >
> > > Peter
> > > ----- Original Message -----
> > > From: "Andreas Vallen" <vallen@gmx.net>
> > > To: <mail@peterbe.com>
> > > Sent: Friday, May 18, 2001 4:51 AM
> > > Subject: DTML/ZPT examples
> > >
> > > > Hi,
> > > >
> > > > I just looked at your DTML vs. ZPT page.
> > > > I think I've found an error in your second example.
> > > > If the condition in the ZPT example evaluates to
> > > > true then the whole tag gets replaced - including
> > > > the "<h4>" which does not happen in the DTML example.
> > > > We get the same output by replacing
> > > > "tal:replace" with "tal:content."
> > > >
> > > > DTML:
> > > > <dtml-if "_.len(result)==0">
> > > >   <H4>Monkey!!</H4>
> > > > </dtml-if>
> > > >
> > > > ZPT:
> > > > <H4 tal:replace="template/title"
> > > >     tal:condition="python:len(result)==0">
> > > >   Might display Monkey</H4>
> > > >
> > > > Bye,
> > > > Andreas
> 
> 
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