Re: [netmod] enumeration type
Jonathan Hansford <Jonathan@hansfords.net> Wed, 22 January 2014 15:16 UTC
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Date: Wed, 22 Jan 2014 15:15:55 +0000
From: Jonathan Hansford <Jonathan@hansfords.net>
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Subject: Re: [netmod] enumeration type
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On 2014-01-22 12:33, Juergen Schoenwaelder wrote: > On Wed, Jan 22, 2014 at 10:30:41AM +0000, Jonathan Hansford wrote: > >> Can anyone explain why enumerations were originally given values, if >> they have no intrinsic meaning (other than the fact that calling >> them >> enumerations implies that numbers are involved)? > > As far as I recall, they were originally designed this way at the > Stockholm meeting (that is months before the YANG work came to the > IETF) in order to support some coexistance with other protocols that > happen to use numbers instead of strings on the wire for > enumerations. Having looked through some historical documents, it may also have arisen from the draft-bjorklund-yang-requirements-00 response ("SMIv2 style enumerations are fully supported in YANG.") to RFC 3216 "SMIng Objectives", section 4.1.17 "Enumerations": Type: basic From: SMI, SPPI Description: SMIng must provide support for enumerations. Enumerated values must be a part of the enumeration definition. Motivation: SMIv2 already has enumerated numbers. Notes: Enumerations have the implicit constraint that the attribute is constrained to the values for the enumeration. > > Looking at it from today's perspective, I tend to believe the > automatic assignment of values was not a very smart choice (since > using it is very dangerous when it comes to updates) and in hindsight > it might have been better to allow values as an optional feature of > an > enum that YANG data model designers can use but are not required to > use. > > /js > > PS: I do feel somewhat guilty for this design but I am not sure who > actually had this automated numbering idea and it probably does > not matter. Back in London, I started coding what several years > later became RFC 6643, but for that I did not need automated > numbering.
- Re: [netmod] enumeration type Randy Presuhn
- [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Jernej Tuljak
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Martin Bjorklund
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Jernej Tuljak
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Jonathan Hansford
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Per Hedeland
- Re: [netmod] enumeration type Randy Presuhn
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Per Hedeland
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Per Hedeland
- Re: [netmod] enumeration type Jernej Tuljak
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Jonathan Hansford
- Re: [netmod] enumeration type Per Hedeland
- Re: [netmod] enumeration type Jonathan Hansford
- Re: [netmod] enumeration type Per Hedeland
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Xiang Li
- Re: [netmod] enumeration type Jonathan Hansford
- Re: [netmod] enumeration type David Spakes
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type B Lukovic
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type B Lukovic
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type B Lukovic
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Martin Bjorklund
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type B Lukovic
- Re: [netmod] enumeration type Juergen Schoenwaelder
- Re: [netmod] enumeration type David Spakes
- Re: [netmod] enumeration type David Harrington
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Randy Presuhn
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type Ladislav Lhotka
- Re: [netmod] enumeration type Martin Bjorklund
- Re: [netmod] enumeration type Andy Bierman
- Re: [netmod] enumeration type B Lukovic