Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Kent and I discussed this.  We (as chairs) don't think there is currently WG consensus on RegEx guidelines.  We do think there is sufficient interest to continue the discussion, and would like to do so both on list and in our next meeting in Singapore. Thank you, Lou and Kent On 9/6/2017 1:01

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Wed, Sep 6, 2017 at 2:16 AM, Robert Wilton wrote: > > > On 05/09/2017 19:00, Juergen Schoenwaelder wrote: > >> On Tue, Sep 05, 2017 at 06:17:09PM +0100, Robert Wilton wrote: >> >>> I believe that tools intended for general use should follow the YANG spec literally.

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 05/09/2017 19:00, Juergen Schoenwaelder wrote: On Tue, Sep 05, 2017 at 06:17:09PM +0100, Robert Wilton wrote: I believe that tools intended for general use should follow the YANG spec literally. I don't fully agree.  I think that they only need to cover the parts of the YANG spec for the

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 06/09/2017 09:33, Ladislav Lhotka wrote: Robert Wilton píše v St 06. 09. 2017 v 08:52 +0100: Hi Lou, This is the addition to 6087bis that I propose. Note, this is the same text in my email on the 31st of August. I propose adding the following 2 paragraphs to 6087bis section on pattern

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Robert Wilton píše v St 06. 09. 2017 v 08:52 +0100: > Hi Lou, > > This is the addition to 6087bis that I propose. Note, this is the same > text in my email on the 31st of August. > > I propose adding the following 2 paragraphs to 6087bis section on > pattern and ranges: > > NEW: > To ensure

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Lou, This is the addition to 6087bis that I propose.   Note, this is the same text in my email on the 31st of August. I propose adding the following 2 paragraphs to 6087bis section on pattern and ranges: NEW: To ensure patterns are easy to read and implement, authors SHOULD restrict

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Juergen Schoenwaelder píše v Út 05. 09. 2017 v 20:00 +0200: > On Tue, Sep 05, 2017 at 06:17:09PM +0100, Robert Wilton wrote: > > > > > I believe that tools intended for general use should follow the YANG spec > > > literally. > > > > I don't fully agree. I think that they only need to cover the

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Rob, (as chair) On 9/5/2017 1:17 PM, Robert Wilton wrote: > However, I have thrown in the towel on my regex crusade. I'm sorry, I've lost the thread here a bit. in order to guage consensus on this topic, it would be helpful to send the latest text that you are proposing for inclusion in the the

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Tue, Sep 05, 2017 at 06:17:09PM +0100, Robert Wilton wrote: > > > I believe that tools intended for general use should follow the YANG spec > > literally. > > I don't fully agree.  I think that they only need to cover the parts of the > YANG spec for the models that they are using (or might

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 05/09/2017 17:35, Ladislav Lhotka wrote: Robert Wilton píše v Po 04. 09. 2017 v 17:07 +0100: Hi Lada, On 04/09/2017 15:59, Ladislav Lhotka wrote: Robert Wilton píše v Po 04. 09. 2017 v 15:05 +0100: Hi Andy, On 02/09/2017 17:46, Andy Bierman wrote: On Sat, Sep 2, 2017 at 4:28 AM,

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Robert Wilton píše v Po 04. 09. 2017 v 17:07 +0100: > Hi Lada, > > On 04/09/2017 15:59, Ladislav Lhotka wrote: > > Robert Wilton píše v Po 04. 09. 2017 v 15:05 +0100: > > > Hi Andy, > > > > > > On 02/09/2017 17:46, Andy Bierman wrote: > > > > On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Mon, Sep 4, 2017 at 9:22 AM, Robert Wilton wrote: > > > On 04/09/2017 16:55, Andy Bierman wrote: > > > > On Mon, Sep 4, 2017 at 7:05 AM, Robert Wilton wrote: > >> Hi Andy, >> >> On 02/09/2017 17:46, Andy Bierman wrote: >> >> >> >> On Sat, Sep 2, 2017 at

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 04/09/2017 16:55, Andy Bierman wrote: On Mon, Sep 4, 2017 at 7:05 AM, Robert Wilton > wrote: Hi Andy, On 02/09/2017 17:46, Andy Bierman wrote: On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Lada, On 04/09/2017 15:59, Ladislav Lhotka wrote: Robert Wilton píše v Po 04. 09. 2017 v 15:05 +0100: Hi Andy, On 02/09/2017 17:46, Andy Bierman wrote: On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder wrote: On Sat, Sep 02, 2017 at 10:39:57AM

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Mon, Sep 4, 2017 at 7:05 AM, Robert Wilton wrote: > Hi Andy, > > On 02/09/2017 17:46, Andy Bierman wrote: > > > > On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder < > j.schoenwael...@jacobs-university.de> wrote: > >> On Sat, Sep 02, 2017 at 10:39:57AM +, Acee

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Robert Wilton píše v Po 04. 09. 2017 v 15:05 +0100: > Hi Andy, > > On 02/09/2017 17:46, Andy Bierman wrote: > > > > On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder > > wrote: > > > On Sat, Sep 02, 2017 at 10:39:57AM +, Acee Lindem (acee) wrote: >

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Carsten, I'm slightly lost :-) Don't you have the same issue for CDDL in that the specification supports the full syntax from PCRE (which appears to be one of the much larger and more complex regex language specifications) which will force implementations to use a PCRE compatible

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Andy, On 02/09/2017 17:46, Andy Bierman wrote: On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder > wrote: On Sat, Sep 02, 2017 at 10:39:57AM +, Acee Lindem (acee) wrote: > > This is

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

I’m not going to say we have solved the underlying problem (too many flavors of regular expression) completely for CDDL, but in CDDL we are using PCRE with anchors then added: https://tools.ietf.org/html/draft-ietf-cbor-cddl-00#section-3.8.3 (And here is the implementation: h[k] =

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Juergen, On 02/09/2017 08:33, Juergen Schoenwaelder wrote: On Fri, Sep 01, 2017 at 10:45:51AM +0100, Robert Wilton wrote: Hi Alex, On 01/09/2017 00:57, Alex Campbell wrote: Hi, I'd be very wary of adding guidelines that restrict the regex syntax. A tool that supports YANG must

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Sat, Sep 2, 2017 at 4:28 AM, Juergen Schoenwaelder < j.schoenwael...@jacobs-university.de> wrote: > On Sat, Sep 02, 2017 at 10:39:57AM +, Acee Lindem (acee) wrote: > > > > This is not an effort to change or bifurcate the YANG 1.1. It is simply > to > > RECOMMEND a proper subset of XSD

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Sat, Sep 02, 2017 at 10:39:57AM +, Acee Lindem (acee) wrote: > > This is not an effort to change or bifurcate the YANG 1.1. It is simply to > RECOMMEND a proper subset of XSD pattern that is more portable. > If you implement YANG as it is defined, pattern are portable. Given this, I do

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Juergen, On 9/2/17, 3:33 AM, "netmod on behalf of Juergen Schoenwaelder" wrote: >On Fri, Sep 01, 2017 at 10:45:51AM +0100, Robert Wilton wrote: >> Hi Alex, >> >> >> On 01/09/2017 00:57, Alex Campbell wrote: >> > >> >

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Wed, Aug 30, 2017 at 05:44:01PM +0100, Robert Wilton wrote: > > First question: How many pattern statements in draft and standard IETF YANG > modules actually use Unicode properties (e.g \p{}). > Answer: Just 2.  To add a zone at the end of the IPv4/IPv6 address. > > E.g.   pattern >  

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Fri, Sep 01, 2017 at 10:45:51AM +0100, Robert Wilton wrote: > Hi Alex, > > > On 01/09/2017 00:57, Alex Campbell wrote: > > > > Hi, > > > > > > I'd be very wary of adding guidelines that restrict the regex syntax. > > > > > > A tool that supports YANG must implement the full regex

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

m:* netmod <netmod-boun...@ietf.org> on behalf of Robert Wilton <rwil...@cisco.com> *Sent:* Thursday, 31 August 2017 4:44 a.m. *To:* Andy Bierman; Juergen Schoenwaelder; Xufeng Liu; netmod@ietf.org *Subject:* Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines Hi, On

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

g Subject: Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines Hi, On 30/08/2017 15:52, Andy Bierman wrote: On Wed, Aug 30, 2017 at 5:31 AM, Juergen Schoenwaelder <j.schoenwael...@jacobs-university.de<mailto:j.schoenwael...@jacobs-university.de>> wrote: On Wed, Aug 30

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi, The burden this would place on YANG writers would be excessive. We learned in SNMP-land about CLRs (clever little rules) and how they need to be avoided. We learned that special-casing and sub-setting technology has its own costs, which are usually more than the problem they solved (e.g.,

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Rob Speaking as a contributor. On August 30, 2017 12:44:42 PM Robert Wilton wrote: Hi, On 30/08/2017 15:52, Andy Bierman wrote: On Wed, Aug 30, 2017 at 5:31 AM, Juergen Schoenwaelder >

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

As Andy says, readability is #1, and it follows that a restricted subset would be more understandable. Standardizing this would require an update to RFC 7950 (read: not going to happen anytime soon). Maybe we could start with just having a tool detect when something outside the common-subset

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi, On 30/08/2017 15:52, Andy Bierman wrote: On Wed, Aug 30, 2017 at 5:31 AM, Juergen Schoenwaelder > wrote: On Wed, Aug 30, 2017 at 12:48:19PM +0100, Robert Wilton wrote: > > > On

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Wed, Aug 30, 2017 at 5:31 AM, Juergen Schoenwaelder < j.schoenwael...@jacobs-university.de> wrote: > On Wed, Aug 30, 2017 at 12:48:19PM +0100, Robert Wilton wrote: > > > > > > On 30/08/2017 11:29, Juergen Schoenwaelder wrote: > > > On Wed, Aug 30, 2017 at 10:16:30AM +0100, Robert Wilton wrote:

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Wed, Aug 30, 2017 at 12:48:19PM +0100, Robert Wilton wrote: > > > On 30/08/2017 11:29, Juergen Schoenwaelder wrote: > > On Wed, Aug 30, 2017 at 10:16:30AM +0100, Robert Wilton wrote: > > > Hi Andy, > > > > > > What I am suggesting makes it easier for readers, because I am a proponent > > >

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 30/08/2017 11:29, Juergen Schoenwaelder wrote: On Wed, Aug 30, 2017 at 10:16:30AM +0100, Robert Wilton wrote: Hi Andy, What I am suggesting makes it easier for readers, because I am a proponent of simpler regular expressions that are easy to read and understand. For example, I wonder how

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Wed, Aug 30, 2017 at 10:16:30AM +0100, Robert Wilton wrote: > Hi Andy, > > What I am suggesting makes it easier for readers, because I am a proponent > of simpler regular expressions that are easy to read and understand. > > For example, I wonder how many YANG model readers would immediately

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi Andy, What I am suggesting makes it easier for readers, because I am a proponent of simpler regular expressions that are easy to read and understand. For example, I wonder how many YANG model readers would immediately comprehend what this pattern statement means: pattern

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Hi, I agree with Juergen that these proposed guidelines are not a good idea. The priority order for YANG is (1) readers (2) writers and (3) toolmakers. It seems trivial for group (3) to convert the XSD pattern to some other format. It seems difficult to train all the people in groups (1) and (2)

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 28/08/2017 16:46, Juergen Schoenwaelder wrote: On Mon, Aug 28, 2017 at 12:58:59PM +, Xufeng Liu wrote: [Xufeng] [0..9] is still compliant with the XSD pattern specified by YANG 1.0 and 1.1. Using [0..9] instead of [\d] will make the implementations with native POSIX RegEx easier without

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Tue, Aug 29, 2017 at 09:39:05AM +0200, Benoit Claise wrote: > In this discussion, let's keep in mind that the openconfig modules use the > POSIX regex while the IETF uses the W3C regex. > So for operators that have to deal with a mix of openconfig and IETF > modules, this type of advice could

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

In this discussion, let's keep in mind that the openconfig modules use the POSIX regex while the IETF uses the W3C regex. So for operators that have to deal with a mix of openconfig and IETF modules, this type of advice could be handy from a tooling point of view. Such advice, if not in

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Mon, Aug 28, 2017 at 12:58:59PM +, Xufeng Liu wrote: > > [Xufeng] [0..9] is still compliant with the XSD pattern specified by > YANG 1.0 and 1.1. Using [0..9] instead of [\d] will make the > implementations with native POSIX RegEx easier without the need for > a tool to inspect every

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

; 'netmod@ietf.org' <netmod@ietf.org> > Subject: Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines > > On Fri, Aug 25, 2017 at 12:40:18PM +, Xufeng Liu wrote: > > > > > I did not see a proposed change to the standard YANG specification > > > re

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

> -Original Message- > From: Carsten Bormann [mailto:c...@tzi.org] > Sent: Thursday, August 24, 2017 2:11 PM > To: Xufeng Liu <xufeng_...@jabil.com> > Cc: netmod@ietf.org > Subject: Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines > > On

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

> -Original Message- > From: Per Hedeland [mailto:p...@tail-f.com] > Sent: Thursday, August 24, 2017 1:15 PM > To: Ladislav Lhotka <lho...@nic.cz> > Cc: 'netmod@ietf.org' <netmod@ietf.org>; Xufeng Liu <xufeng_...@jabil.com> > Subject: Re: [netmod] Pote

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On Aug 23, 2017, at 23:20, Xufeng Liu wrote: > > 1.2.2. Avoid Unicode Characters > > Unicode characters are allowed in XSD regular expressions, but are not > supported in the POSIX variant. If possible, the model designers SHOULD avoid > using Unicode characters, such

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

On 2017-08-24 17:54, Ladislav Lhotka wrote: > Per Hedeland writes: > >> I strongly agree with all of Juergen's statements, and disagree also >> with the suggestion to include the parts of the text that he didn't >> specifically disagree with. And I'd like to add that the "lack

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

Per Hedeland writes: > I strongly agree with all of Juergen's statements, and disagree also > with the suggestion to include the parts of the text that he didn't > specifically disagree with. And I'd like to add that the "lack of XSD > support" argument is pretty weak - there

Re: [netmod] Potential additions to rfc6087bis: RegEx guidelines

I strongly agree with all of Juergen's statements, and disagree also with the suggestion to include the parts of the text that he didn't specifically disagree with. And I'd like to add that the "lack of XSD support" argument is pretty weak - there exists at least one freely available

[netmod] Potential additions to rfc6087bis: RegEx guidelines

Members of Routing Area Yang DT have had some discussions about the handling of various variants of regular expressions. The followings are the current state, and we are thinking that if this topic can be added to RFC6087bis: 1. Regular Expression Usage YANG uses regular expressions to restrict