[Zope3-Users] Re: formlib vs. cancel button

[Martin Aspeli]

Marius Gedminas wrote:

> I'd be happy to implement and commit something

Yay!

> but I'd be happier if
> someone else designed the API.  When I try to design APIs myself, I tend
> to change my mind too often.  Now I want
> 
>     @form.action("Cancel", validator=None)
> 
> to mean "do no validation".  But perhaps that's not backwards-compatible
> enough?

+1 This sounds sensible and intuitive and non-invasive. It was the first 
thing I tried. :)

 From my original debugging, I think the problem is that when 
validator=None in formlib, it falls back on some default validator. I 
suggest that the "default" validator is some _marker, e.g.

_marker = object

def action(name, ..., validator=_marker):
    ...

...

    if validator is _marker:
        validator = default_validator

Or some such. The only thing that'd break, probably, would be people who 
*explicitly* set validator=None and expected the default validator, 
which sounds like a pretty marginal case to me.

Martin