class ActiveModel::Serializer::Reflection

def value(serializer, include_slice)
  @object = serializer.object
  @scope = serializer.scope
  block_value = instance_exec(serializer, &block) if block
  return unless include_data?(include_slice)
  if block && block_value != :nil
    block_value
  else
    serializer.read_attribute_for_serialization(name)
  end
end