# File lib/cgikit/api.rb, line 97
  def optional_attributes( component, associations, prefix = nil )
    attrs = {}
    associations.each do |key, as|
      if !has_binding?(key) and !special_binding_key?(key) then
        if prefix.nil? or (prefix and /\A#{prefix}/ === key.to_s) then
          attrs[key] = as.value(component)
        end
      end
    end
    attrs
  end