Re: Fuzzy words [was Uppercase question for RFC2119 words]

John C Klensin <john-ietf@jck.com> Tue, 29 March 2016 16:43 UTC

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Date: Tue, 29 Mar 2016 12:34:22 -0400
From: John C Klensin <john-ietf@jck.com>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>, "Scott O. Bradner" <sob@sobco.com>, Barry Leiba <barryleiba@computer.org>
Subject: Re: Fuzzy words [was Uppercase question for RFC2119 words]
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--On Tuesday, March 29, 2016 08:58 +1300 Brian E Carpenter
<brian.e.carpenter@gmail.com> wrote:

>...
> The other words (must, shall, required, not) mean what they
> always mean. The only argument for upper-casing them is
> aesthetic symmetry. If a spec uses alternatives like
> mandatory, necessary or forbidden, they are just as powerful.
>...

Actually, when 2119 is referenced, Section 6 attaches particular
interoperability semantics to MUST, SHALL, etc., that are not
part of the plain-English meaning of those words.  Section 6
seems to be ignored most of the time but cited when it supports
an axe someone wants to grind about use of conformance language.

    john