[html-formfu] Conditional constraints

[Ronald J Kimball]

I'm curious about what would be best practice for doing "conditional 
constraints", such as: if fieldA's value is 'foo', then fieldB is 
required; or if fieldA's value is 'bar', then fieldB must have the value 
'baz'.  Have other people had to do something like this?  What would be 
a good way to accomplish it?

Perhaps a constraint derived from HTML::FormFu::Constraint::_others, 
with some additional configuration available...

thanks,
Ronald