# File lib/json-schema/validator.rb, line 129
    def load_ref_schema(parent_schema, ref)
      schema_uri = absolutize_ref_uri(ref, parent_schema.uri)
      return true if self.class.schema_loaded?(schema_uri)

      schema = @options[:schema_reader].read(schema_uri)
      self.class.add_schema(schema)
      build_schemas(schema)
    end