def for_buffer
      self.class.buffer_option_keys.inject({}) do |hash, key|
        value = public_send(key)
        if self.class.buffer_defaults[key] != value
          hash[key] = value
        end
        hash
      end
    end
def for_buffer
      self.class.buffer_option_keys.inject({}) do |hash, key|
        value = public_send(key)
        if self.class.buffer_defaults[key] != value
          hash[key] = value
        end
        hash
      end
    end
Returns a non-default subset of options: those that {Haml::Buffer} cares about.
 All of the values here are such that when `#inspect` is called on the hash,
 it can be `Kernel#eval`ed to get the same result back.

 See {file:REFERENCE.md#options the Haml options documentation}.

 @return [{Symbol => Object}] The options hash