Re: [abnf-discuss] Target audience for ABNF

Dave Crocker <> Mon, 20 November 2017 00:54 UTC

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To: Paul Kyzivat <>,
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From: Dave Crocker <>
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Date: Sun, 19 Nov 2017 16:54:08 -0800
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Subject: Re: [abnf-discuss] Target audience for ABNF
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On 11/19/2017 4:19 PM, Paul Kyzivat wrote:
> On 11/19/17 4:08 PM, Carsten Bormann wrote:
>>> On Nov 19, 2017, at 19:56, Dave Crocker <> wrote:
>>> Computers are not the target audience for computer languages.  Human 
>>> readers are.
>> +10k.
> I agree that the human audience is of major importance.
> But mechanical verifiability of ABNF is also important.

I of course do not mean that computers are irrelevant.  However 
'verifiability' invokes formal methods and those typically aren't a 
concern for typical specification efforts.  Machine processing, yes. 
Mathematical proofs, no.

I gather you are claiming otherwise.  I haven't noticed any history of 
formal verification for IETF-related specifications, so perhaps you have 
some pointers?

> Ideally IdNits would verify ABNF in drafts as a matter of course. IIUC 
> doing so has been included as a requirement for the new tooling. Given 
> the current situation what IdNits can potentially do is very limited.

IdNits hardly seems to qualify as 'verification'.  So I'm probably not 
understanding exactly what problem you are concerned about.  Details?


Dave Crocker
Brandenburg InternetWorking