check_for_circular_references

# File activesupport/lib/active_support/json/encoding.rb, line 55
          def check_for_circular_references(value)
            if @seen.any? { |object| object.equal?(value) }
              raise CircularReferenceError, 'object references itself'
            end
            @seen.unshift value
            yield
          ensure
            @seen.shift
          end