# File lib/mongoid/fields.rb, line 229
      def add_field(name, options = {})
        meth = options.delete(:as) || name
        type = options[:localize] ? Fields::Serializable::Localized : options[:type]
        Mappings.for(type, options[:identity]).instantiate(name, options).tap do |field|
          fields[name] = field
          defaults << name unless field.default_val.nil?
          create_accessors(name, meth, options)
          process_options(field)
          define_attribute_method(name)
        end
      end