Introspection rules example

gistfile1.py

class RegexField(CharField):
    def __init__(self, regex=None, *args, **kwargs):
        self.regex = regex
        super(CharField,self).__init__(*args, **kwargs)

    def formfield(self, **kwargs):
        from django import forms
        defaults = {
            'form_class': forms.RegexField,
            'regex': self.regex,
        }
        defaults.update(kwargs)
        return super(CharField, self).formfield(**defaults)
        
# South introspection rules
from south.modelsinspector import add_introspection_rules
rules = [
  (
    # Which classes this rule applies to
    (RegexField,),
    # Rules to recover positional args
    [],
    # Rules to recover named args
    {
        "regex": ["regex", {'default':None}],
    },
  ), 
]    
 
add_introspection_rules(rules, ['^tariffx\.fields\.RegexField',])