[Zope-dev] Stumped about handling this particular exception...

[Jim Fulton]

Amos Latteier wrote:
> 

(snip)

> It may be that ZPublisher doesn't have much business validating form input.

I agree. ;)

> When I complain to Jim Fulton that the converters are pretty lame he
> usually tells me that they are not for form validation, but for argument
> marshalling.

Exactly.  Input validation, error reporting, and other UI activities
should be done at a much higher level.  ZPublisher is a very low-level
tool meant for basic communication.

Obviously, we made the mistake early on of introducting "required", 
which really is an input validation feature.  This was before we realized
that we couldn't hope to do a good job of validation at such a low level.

 
> Improving the ZPublisher converters is a worthwhile problem, IMO.

I agree,  It would be nice to do more sophisticated marshalling. ;)

> In
> addition, making ZPublisher's error reporting more flexible is also a
> worthwhile project.

Well, It would be worthwhile to make ZPublisher provide better hooks
to let application handle errors detected by ZPublisher.  This is
definately on the to do list.

I also think that a default value mechanism of some kind would 
make sense.  This would help in other situations too.

Jim

--
Jim Fulton           mailto:jim@digicool.com
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