W3C home > Mailing lists > Public > public-css-archive@w3.org > December 2020

Re: [csswg-drafts] css should define and use consistent terminology for words like "deprecated", "obsolete" (#5644)

From: Michael[tm] Smith via GitHub <sysbot+gh@w3.org>
Date: Wed, 09 Dec 2020 23:02:12 +0000
To: public-css-archive@w3.org
Message-ID: <issue_comment.created-742118283-1607554931-sysbot+gh@w3.org>
> What's required for conformance or not is a separate question represented via RFC2119 terminology.

At https://html.spec.whatwg.org/multipage/introduction.html#conformance-requirements-for-authors the HTML spec explains how it defines conformance requirements for authors and documents as a conformance class, and explains that the spec defines conformance requirements for distinguishing between a conforming document and non-conforming document. 

And the HTML spec uses RFC2119 terminology to specify those document/authoring conformance requirements.
In particular, the HTML spec defines some document/authoring conformance requirements as cases that MUST NOT be used by documents/authors, and some others as cases that instead SHOULD NOT be used by documents/authors.

For the set of CSS specs, is there somewhere a similar explanation of whether CSS defines requirements for documents/authors as a conformance class?

If a CSS spec states that a particular feature is _deprecated_, does that mean authors MUST NOT use that feature, or does it mean that authors SHOULD NOT use that feature? Does a CSS feature marked as _obsolete_ mean that authors MUST NOT use that feature, or does it mean that authors SHOULD NOT use that feature?

It seems like CSS specs do actually intend to define conformance requirements for documents/authors. And therefore it seems useful for there to be an explanation somewhere among the set of specs — similar to what the HTML spec has — that explicitly addresses document/authoring conformance requirements.

And along with that, if the terms _deprecated_ and _obsolete_  are intended to have some effect on what documents/authors must not do or should not do, then it seems like the intended effect of those terms for documents/authors should be explicitly and unambiguously stated somewhere.

As a maintainer of conformance-checking tools, I have a very practical need for those terms to be unambiguously defined — and in general, for the CSS specs to be unambiguous about identifying things that documents/authors MUST NOT have, and identifying things that documents/authors SHOULD NOT have, and unambiguously distinguishing between the two.

In practical terms, what the distinction means for me and other developers of conformance-checking tools is that if a CSS spec defines a case as a MUST NOT, then we make our conformance-checkers report an error for any instance of that — and for SHOULD NOT cases, we instead report just a warning.

So as a conformance-checker developer, ultimately what I want for any case of the terms _deprecated_ and _obsolete_ in a CSS spec is to clearly know: Do I make my conformance checker report an error for that case? Or do I make it report a warning?

And I’d like to be able to trust that the set of CSS specs are using those terms consistently, based on precise meanings defined somewhere, and with some formal statement somewhere in the set of CSS specs that explains how I can tell the difference between a case that a CSS spec intends MUST NOT be used by documents/authors versus a case that a CSS spec instead intends SHOULD NOT be used by documents/authors.

GitHub Notification of comment by sideshowbarker
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/5644#issuecomment-742118283 using your GitHub account

Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Wednesday, 9 December 2020 23:02:14 UTC

This archive was generated by hypermail 2.4.0 : Tuesday, 5 July 2022 06:42:23 UTC