[Zope] change variable

[Paul Winkler]

On Tue, Jul 23, 2002 at 06:17:45PM +0100, Ben Avery wrote:
> I agree with Charlie, I think DTML has been designed not to make it easy 
> to do any kind of business logic. Zope Page Templates are more recent, 
> and have even less capacity for programming logic.

I think that was a deliberate decision, to encourage further
separation of logic and presentation, possibly inspired by
the recurring threads like "How do I do 10,000 things in my DTML
document" which inevitably lead to some really confusing
dtml code suggestions.  Divide and conquer...

> I'm newish to Zope myself, but for any development I do now, I only use 
> DTML for presentation itself.
> For each page of the site I'm developing, I have a Python script, e.g. 
> calendar_view_handler to take any form inputs from the previous page, 
> use things from the session, call and use ZSQL methods, and put 
> everything I need for the next page, in nice data structures into the 
> request object, then call the DTML method, e.g. calendar_view_display, 
> which only uses DTML variables to loop over data structures, and maybe 
> do simple 'this or that' splits if I absolutely have to.
> This allows a clean separation of logic and presentation, and means you 
> don't have this constant wrestle against the limitations of DTML.
> Using Python is actually a lot easier than using DTML - don't be scared 
> by it, it's the easiest language to learn I've come across :)

Hear, hear. You're lucky that you got the idea early.
I think many Zope newbies are put off by the thought of learning
a templating language *and* a programming language. But it's really
the right way to approach Zope. Everything becomes so much nicer.
Remember, the O stands for Object... and any good object-oriented
designer appreciates low coupling and high cohesion.

Any Zope developers who don't recognize those phrases are highly
encouraged to go look them up. Light bulbs will appear over
your head when it sinks in.

-- 

Paul Winkler
home:  http://www.slinkp.com
"Muppet Labs, where the future is made - today!"