How to make sure at least one checkbox is checked?

I've got a list of checkboxes, each with the same name and the value
attribute is an integer between 1 and 10.

Right now, I'm converting this to a list like this:

    from formencode import validators
    validators.ForEach(validators.Int(), convert_to_list=True)

I'd like to add another validator to make sure at least one checkbox is
checked, but I can't figure out how to do that.

Any suggestions?

Matt


-- 
Matthew Wilson
[email protected]
http://tplus1.com
216-470-6058

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