Here is a list of all documented variables with links to the class documentation for each member:

- n -

NA : core\check\result
NAME_MAX_LENGTH : xmldb_field, xmldb_table
NAME_PREFIX : base_setting_ui
NEVER_RUN_TIME : core\task\scheduled_task
NO_GROUPS_ALLOWED : mod_quiz\local\reports\report_base
NO_OUTPUT : tool_uploadcourse_tracker
NO_OWNER_ID : core_search\manager
NO_PRIORITY : data_field_base
NODETYPE_BRANCH : navigation_node
NODETYPE_LEAF : navigation_node
NON_APPROVED_ALL : mod_glossary_entry_query_builder
NON_APPROVED_NONE : mod_glossary_entry_query_builder
NON_APPROVED_ONLY : mod_glossary_entry_query_builder
NON_APPROVED_SELF : mod_glossary_entry_query_builder
NONCORE_PRESET : core_adminpresets\manager
NONVALIDTYPEID : backup_ltiservice_gradebookservices_subplugin
NOOFFICIAL : MoodleQuickForm_tags
NOREPLY_USER : core_user
NOT_CHECKED : core_reportbuilder\local\filters\boolean_select
NOT_EMPTY : core_reportbuilder\local\filters\tags
NOT_ENTERED : tool_brickfield\registration
NOT_EQUAL_TO : core_reportbuilder\local\filters\category, core_reportbuilder\local\filters\select, core_reportbuilder\local\filters\tags
NOT_FOUND : core\event\base
NOT_HIDEABLE : block_contents
NOT_MAPPED : core\event\base
NOT_STANDARD_ONLY : core_tag_tag
NOTIFY_ERROR : core\output\notification
NOTIFY_INFO : core\output\notification
NOTIFY_MAXIMUM_TIME : core\task\send_failed_login_notifications_task
NOTIFY_SUCCESS : core\output\notification
NOTIFY_WARNING : core\output\notification
NOTSET : tool_dataprivacy\context_instance
NOTVISIBLE : core_course\customfield\course_handler, qbank_customfields\customfield\question_handler
NS_SOAP : webservice_soap\wsdl
NS_SOAP_ENC : webservice_soap\wsdl
NS_SOAP_TRANSPORT : webservice_soap\wsdl
NS_WSDL : webservice_soap\wsdl
NS_XSD : webservice_soap\wsdl
NUM_CAPS_FOR_SEARCH : core_role_capability_table_base
NUMBER_MAX_LENGTH : xmldb_field
NUMPER_REVIEWER : workshop_random_allocator_setting
NUMPER_SUBMISSION : workshop_random_allocator_setting