# File lib/autumn/leaf.rb, line 400
    def self.before_filter(filter, options={})
      if options[:only] and not options[:only].kind_of? Array then
        options[:only] = [ options[:only] ]
      end
      if options[:except] and not options[:except].kind_of? Array then
        options[:except] = [ options[:except] ]
      end
      write_inheritable_array 'before_filters', [ [ filter.to_sym, options ] ]
    end