Subject: [netmod] [Errata Verified] RFC6020 (4283)

From: RFC Errata System <[email-masked]>
Date: Wed, 11 Mar 2015 01:46:59 -0700 (PDT)

The following errata report has been verified for RFC6020,
"YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)". 

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=6020&eid=4283

--------------------------------------
Status: Verified
Type: Technical

Reported by: Cesar Crusius <[email-masked]>
Date Reported: 2015-02-28
Verified by: Benoit Claise (IESG)

Section: 12

Original Text
-------------
stmtend = ";" / "{" *unknown_statement "}"

Corrected Text
--------------
stmtend = optsep (";" / "{" stmtsep "}") stmtsep

Notes
-----
Note1: As specified, there are no spaces allowed between the unknown statements, and between the braces and the unknown statements.

Notes2:
The original "stmtend" rule does not allow for spaces between unknown
statements, which requires the "*unknown-statement" fix in "stmtend".

There is at least one place ("revision-date-stmt") where "stmtend" end
is not preceded by "optsep". Instead of fixing those rules, it is better to
include "optsep" in "stmtend" itself, since it should always be present.

On the same note, almost all "stmtend" uses are followed by a
"stmtsep", and any cases where that does not happen are probably an error, so again it is better to make that explicit in the "stmtend" rule itself.

With the change in this errata, there will be a lot of rules in the
ABNF with redundant (but not technically incorrect) "optsep" and "stmtsep" parts, as for example

      module-header-stmts = ;; these stmts can appear in any order
                            [yang-version-stmt stmtsep]
                            namespace-stmt stmtsep
                            prefix-stmt stmtsep

      namespace-stmt = namespace-keyword sep uri-str optsep stmtend

which now could be replaced with

      module-header-stmts = ;; these stmts can appear in any order
                            [yang-version-stmt]
                            namespace-stmt
                            prefix-stmt

      namespace-stmt = namespace-keyword sep uri-str stmtend

These changes should probably be incorporated into the next ABNF
revision.

--------------------------------------
RFC6020 (draft-ietf-netmod-yang-13)
--------------------------------------
Title               : YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)
Publication Date    : October 2010
Author(s)           : M. Bjorklund, Ed.
Category            : PROPOSED STANDARD
Source              : NETCONF Data Modeling Language
Area                : Operations and Management
Stream              : IETF
Verifying Party     : IESG