Re: [netmod] [Editorial Errata Reported] RFC7950 (5642)

On Thu, Feb 21, 2019 at 10:33 AM Martin Bjorklund <mbj@tail-f.com> wrote:

> Andy Bierman <andy@yumaworks.com> wrote:
> > On Thu, Feb 21, 2019 at 10:07 AM Peter Loborg <peter.loborg@ericsson.com
> >
> > wrote:
> >
> > >
> > >
> > > Your example is fine – but the gammar is ch14 specifies something
> > > different:
> > >
> > >
> > >
> > > enum-stmt           = enum-keyword sep string optsep
> > >
> > >                          (";" /
> > >
> > >                           "{" stmtsep
> > >
> > >                               ;; these stmts can appear in any order
> > >
> > >                               *if-feature-stmt
> > >
> > >                               [value-stmt]
> > >
> > >                               [status-stmt]
> > >
> > >                               [description-stmt]
> > >
> > >                               [reference-stmt]
> > >
> > >                            "}") stmtsep
> > >
> > >
> > >
> > > It clearly states  string, not quoted-string. These two have the
> following
> > > rules:
> > >
> > >
> > >
> > > quoted-string       = (DQUOTE string DQUOTE) / (SQUOTE string SQUOTE)
> > >
> > >
> > >
> > > string              = < an unquoted string, as returned by >
> > >
> > >                          < the scanner, that matches the rule >
> > >
> > >                          < yang-string >
> > >
> > >
> > >
> >
> >
> > The text in 9.6.4 is correct.
> > The ABNF is wrong.
>
> No, the ABNF is correct.  The ABNF doens't handle concatenation etc.
> The idea is that the scanner handles quotes and concatenation and
> returns a "string".
>
>

OK -- it is confusing that the rule quoted-string exists, but it
is only for key and leaf-list predicates.

>
> /martin
>
>
Andy

>
>
> >
> >
> >
> > > …and in 6.1.3 we can read that:
> > >
> > >    An unquoted string is any sequence of characters that does not
> > >
> > >    contain any space, tab, carriage return, or line feed characters, a
> > >
> > >    single or double quote character, a semicolon (";"), braces ("{" or
> > >
> > >    "}"), or comment sequences ("//", "/*", or "*/").
> > >
> > >
> > >
> > >    Note that any keyword can legally appear as an unquoted string.
> > >
> > >
> > >
> > > Since the section so clearly writes about single quoted strings and
> double
> > > quoted strings, there can unfortunately be no interpretation that would
> > > allow “identifier” to be called an unquoted string – even though it
> follows
> > > the rules about limited character contents.
> > >
> > >
> > >
> > > Hence – this is not a matter of opinion – it’s a matter of reading
> what’s
> > > actually written in the RFC.
> > >
> > >
> > >
> > > But on the subject of opinion…
> > >
> > >
> > >
> > >       enum "This is also legal";   // should definitely always be
> illegal
> > >
> > >
> > >
> > > …as we cannot create a language binding to enum constructs in any major
> > > programming languages.
> > >
> > >
> > >
> >
> > There are many aspects of YANG that do not map directly to programming
> > languages,
> > such as allowing '.' in identifiers.
> >
> >
> >
> > > Br,
> > >
> > > Peter
> > >
> >
> >
> > Andy
> >
> >
> > >
> > >
> > >
> > >
> > > *From:* Andy Bierman <andy@yumaworks.com>
> > > *Sent:* den 21 februari 2019 18:45
> > > *To:* Martin Bjorklund <mbj@tail-f.com>
> > > *Cc:* RFC Editor <rfc-editor@rfc-editor.org>; Ignas Bagdonas <
> > > ibagdona@gmail.com>; NetMod WG <netmod@ietf.org>; Peter Loborg <
> > > peter.loborg@ericsson.com>; Warren Kumari <warren@kumari.net>
> > > *Subject:* Re: [netmod] [Editorial Errata Reported] RFC7950 (5642)
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > On Thu, Feb 21, 2019 at 8:53 AM Martin Bjorklund <mbj@tail-f.com>
> wrote:
> > >
> > > RFC Errata System <rfc-editor@rfc-editor.org> wrote:
> > > > The following errata report has been submitted for RFC7950,
> > > > "The YANG 1.1 Data Modeling Language".
> > > >
> > > > --------------------------------------
> > > > You may review the report below and at:
> > > > http://www.rfc-editor.org/errata/eid5642
> > > >
> > > > --------------------------------------
> > > > Type: Editorial
> > > > Reported by: Peter Loborg <peter.loborg@ericsson.com>
> > > >
> > > > Section: 9.6.4
> > > >
> > > > Original Text
> > > > -------------
> > > > It takes as an argument a string that is the assigned name.
> > > >
> > > > Corrected Text
> > > > --------------
> > > > It takes as an argument an unquoted string that is the assigned name.
> > >
> > > This is not correct.  The enum argument is not different from any
> > > other keyword's arguments in YANG.  See e.g. the example in 9.12.4:
> > >
> > >        type enumeration {
> > >          enum "unbounded";
> > >        }
> > >
> > > The following is also legal:
> > >
> > >          enum "unb" + 'ounded';
> > >
> > >
> > >
> > >
> > >
> > >   enum "This is also legal";
> > >
> > >
> > >
> > > 9.6.4.  The "enum" Statement
> > >
> > >
> > >
> > >    The "enum" statement, which is a substatement to the "type"
> > >
> > >    statement, MUST be present if the type is "enumeration".  It is
> > >
> > >    repeatedly used to specify each assigned name of an enumeration
> type.
> > >
> > >    It takes as an argument a string that is the assigned name.  *The*
> > >
> > > *   string MUST NOT be zero-length and MUST NOT have any leading or*
> > >
> > > *   trailing whitespace characters* (any Unicode character with the
> > >
> > >    "White_Space" property).  The use of Unicode control codes SHOULD be
> > >
> > >    avoided.
> > >
> > >
> > >
> > >
> > >
> > > This errata should be rejected.
> > >
> > >
> > >
> > > /martin
> > >
> > >
> > >
> > >
> > >
> > > Andy
> > >
> > >
> > >
> > >
> > > >
> > > > Notes
> > > > -----
> > > > Readers are not beeing made aware that careful reading of section
> 6.1.3
> > > and the detailed definition of string in section 14 must be consulted.
> > > > For comming versions of this RFC it would be preferable to use a more
> > > specialized grammar token for these cases (e.g. unquoted-string).
> > > >
> > > > Instructions:
> > > > -------------
> > > > This erratum is currently posted as "Reported". If necessary, please
> > > > use "Reply All" to discuss whether it should be verified or
> > > > rejected. When a decision is reached, the verifying party
> > > > can log in to change the status and edit the report, if necessary.
> > > >
> > > > --------------------------------------
> > > > RFC7950 (draft-ietf-netmod-rfc6020bis-14)
> > > > --------------------------------------
> > > > Title               : The YANG 1.1 Data Modeling Language
> > > > Publication Date    : August 2016
> > > > Author(s)           : M. Bjorklund, Ed.
> > > > Category            : PROPOSED STANDARD
> > > > Source              : Network Modeling
> > > > Area                : Operations and Management
> > > > Stream              : IETF
> > > > Verifying Party     : IESG
> > > >
> > >
> > > _______________________________________________
> > > netmod mailing list
> > > netmod@ietf.org
> > > https://www.ietf.org/mailman/listinfo/netmod
> > >
> > >
>