eventespresso / event-espresso-core

            }

        } else {

            //this thing doesn't exist in the DB,  so just cache it

            if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {

                throw new EE_Error(

                    sprintf(

                        esc_html__(

                            'Before a model object is saved to the database, calls to _add_relation_to must be passed an actual object, not just an ID. You provided %s as the model object to a %s',

                            'event_espresso'

                        ),

                        $otherObjectModelObjectOrID,

                        get_class($this)

                    )

                );

            }

            $otherObject = $otherObjectModelObjectOrID;

            $this->cache($relationName, $otherObjectModelObjectOrID, $cache_id);

        }

            $name,

            $require_construction_to_be_finalized

        );

        if (! $subsection instanceof EE_Form_Section_Proper) {

            throw new EE_Error(

                sprintf(

                    esc_html__(

                        "Subsection '%'s is not an instanceof EE_Form_Section_Proper on form '%s'",

                        'event_espresso'

                    ),

                    $name,

                    get_class($this)

                )

            );

        }

        return $subsection;

    }