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  module ietf-yang-metadata {

    yang-version 1;


    prefix md;

      "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

      "WG Web:   <>

WG List:  <>

WG Chair: Lou Berger

WG Chair: Kent Watsen

Editor:   Ladislav Lhotka

      "This YANG module defines an 'extension' statement that allows
for defining metadata annotations.

Copyright (c) 2016 IETF Trust and the persons identified as
authors of the code.  All rights reserved.

Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Simplified BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents

This version of this YANG module is part of RFC 7952
(; see the RFC itself
for full legal notices.";

    revision "2016-08-05" {
      description "Initial revision.";
        "RFC 7952: Defining and Using Metadata with YANG";


    extension annotation {
      argument "name" {
        yin-element false;
        "This extension allows for defining metadata annotations in
YANG modules.  The 'md:annotation' statement can appear only
at the top level of a YANG module or submodule, i.e., it
becomes a new alternative in the ABNF production rule for
'body-stmts' (Section 14 in RFC 7950).

The argument of the 'md:annotation' statement defines the name
of the annotation.  Syntactically, it is a YANG identifier as
defined in Section 6.2 of RFC 7950.

An annotation defined with this 'extension' statement inherits
the namespace and other context from the YANG module in which
it is defined.

The data type of the annotation value is specified in the same
way as for a leaf data node using the 'type' statement.

The semantics of the annotation and other documentation can be
specified using the following standard YANG substatements (all
are optional): 'description', 'if-feature', 'reference',
'status', and 'units'.

A server announces support for a particular annotation by
including the module in which the annotation is defined among
the advertised YANG modules, e.g., in a NETCONF <hello>
message or in the YANG library (RFC 7950).  The annotation can
then be attached to any instance of a data node defined in any
YANG module that is advertised by the server.

XML encoding and JSON encoding of annotations are defined in
RFC 7952.";
  }  // module ietf-yang-metadata