[whatwg] A plea to Hixie to adopt <main>

Sat Nov 17 02:00:59 PST 2012

Hi Ian,

Responses in line.

FYI

For any implementers or other interested parties the <main> element
specification [2] is currently in a call for consensus to publish as a
first public working draft (over at the W3C) [3]

> > On Thu, 8 Nov 2012, Steve Faulkner wrote:
>
> >
> >
> > >
> http://www.w3.org/html/wg/wiki/User:Sfaulkne/main-usecases#Introduction
> >
> > This page has the following:
> >
> > | Enable users to be able to navigate to and recognise the boundaries of
> > | the main content area
> >
> > This is done by <main> (because of the likely authoring failures) no more
> > reliably, and possibly in fact less reliably, than is already possible
> > with things like <aside>.
>

Requiring a the presence of number of elements and having those elements
used correctly, (some of which from anecdotal reports author,s find
difficult to use correctly),  to provide an indication of something else,
appears wholey more prone to failure than using one element that as specced
[2] is clear in its use and based on current authoring practices.

> >
> >
> http://lists.w3.org/Archives/Public/public-whatwg-archive/2012Nov/0067.html
> >
> http://lists.w3.org/Archives/Public/public-whatwg-archive/2012Oct/0162.html
> >
> >
> > | Enable authors to style the main content area of a page specifically.
> >
> > This is already possible with <div>. It would make sense to have a more
> > specific element if there was a cowpath, but there isn't:
>

there is a clear cowpath and the data has been provided.

> > > Agreed that people get markup wrong, I don't agree with your
> supposition
> > > that <main> would be just as prone to mistakes as the other elements
> you
> > > cited.
> >
> > With all due respect, you have to ignore the data to come to that
> > conclusion. Look at your own data: authors put this semantic all over the
> > place. There is _no_ evidence that they'd do better with <main>.
>

I have looked at the data and no they do not put <div id=main content> all
over the place they put it approx 80% of the time in the right place.

> >
> >
> http://lists.w3.org/Archives/Public/public-whatwg-archive/2012Oct/0162.html
> >
> >
> > > Did the year's old previous discussion take into account id value data
> or
> > > skip link data or role=main placement data?
> >
> > I do not recall the specifics. ARIA didn't exist back then, so clearly it
> > wasn't examined, though.
> >
> >
> > > What the relevant new data clearly indicates is that in approx 80% of
> > > cases when authors identify the main area of content it is the part of
> > > the content that does not include header, footer or navigation content.
> >
> > Where do you get this number from?
>

I looked at a couple of hundred pages [1] in the sample that I have added
styling to show the use of id=main or id=content noting the borders and
what content is and is not contained within them.

> >
> > > It also indicates that where skip links are present or role=main is
> used
> > > their position correlates highly with the use of id values designating
> > > the main content area of a page.
> >
> > How do you determine this correlation? (Are you just using the word
> > colloquially?)
> >
> > What does this correlation mean? Are they all using both incorrectly?
> > (That would get you good correlation too.)
> >
> > What about pages that do not give skip links or role=main? (Pages that
> use
> > those features are going to be disproportionally biased towards competent
> > authors, which makes it dangerous to draw conclusions from that sample.
> >
>

see above , approx 80% I have provided the data set from which my
statements are derived, if you want to disprove them you can analyse the
same data set.

> > > furthermore when ARIA role=main is used in 95% [3] of the cases in the
> > > data sampled it is used once only which is a clear indicator that
> > > authors get how to identify the main content area of a page.
> >
> > I think that's a wildly optimistic conclusion. Lots of pages only use
> > <body> once, that doesn't mean they use it correctly. :-)
>

again I have provided the data set if you disagree you can analyse the data.

> >
> > > *  use of a descriptive id to value to identify the main content area
> of a
> > > web page is common.
> > > (id="main"|id="content"|id="
> > > maincontent"|id="content-main"
>
> |id="main-content"
> > used on 39% of the pages in the sample [2])
>
> As I discuss in the e-mail cited several times above, the area they
> indicate with these IDs is not reliably the "main content". For example,
> it might or might not include the footer, sidebars, navigation links,
> headings, etc.
>

well no, you are making suppositions again, the data set is available for
analysis if you disagree with my conclusions based on my analysis of the
data you can run your own analysis.

>
>
> >  * There is a strong correlation between use of role='main' on an element
> > with id values of 'content' or 'main' or permutations. (when used = 101
> > pages)  77% were on an element with id values of 'content' or 'main' or
> > permutations.
>
> I don't see what this tells us. Obviously if someone is going to mark an
> element as role=main, they'll use the same element for id=main. Doesn't
> mean it's correct use of role=main, nor that it's necessary use. (If they
> can use role=main, seems reasonable to expect them to use modern HTML
> elements too.)
>
>
analyse the data and it shows that in a good majority of cases it is
correct, which is why it is useful information.

>
> > * There is a strong correlation between use of id values of 'content' or
> > 'main' or permutations as targets for 'skip to content'/'skip to main
> > content' links (when used = 67 pages) 78% of skip link targets # were
> > elements with id values of 'content' or 'main' or permutations.
>
> Again, that seems obvious, but doesn't tell us anything useful.
>
>
again,analyse the data and it shows that in a good majority of cases it is
correct, which is why it is useful information.

>
> > * There appears to be a strong correlation in the identification of
> > content areas (with id values of 'content' or 'main' or permutations.)
> > as what is described in the spec as appropriate content to be contained
> > with a <main> element
>
> How do you determine this?
>

again, I manually reviewed a couple of hundred pages form the sample
looking at what content is and is not contained within content areas (with
id values of 'content' or 'main' or permutations.)

> On Wed, 14 Nov 2012, Steve Faulkner wrote:
> >
> > The same can be said for any of the structural semantic elements, what
> > we know is that some authors mark up headings, nav, footer, articles etc
> > incorrectly or not at all.
>
> The difference is that misusing those elements doesn't defeat their
> purpose, while misusing <main> leaves it with no reason for being. The use
> cases for <main> rely on it not being misused by the majority of authors.
> The use cases for things like <aside> benefit from it not being misused,
> but are not lost if other authors misuse them.
>
>
Misusing those elements does defeat their purpose as useful semantic
identifiers for users who benefit from the semantics. It is difficult to
know what other purposes they may or may not have as thee use cases are not
defined in

>
> > What we also know is that user agents do not generally implement
> > heuristics to provide semantic information to users, they rely upon
> > explicit markup to expose semantic structures to convey meaning and
> > provide navigation of content.
>
> The user agents that do the most to get semantics out of HTML pages,
> namely search engines, use absolutely gigantic amounts of heuristics.
>

 the usefulness of the main to search engines has not been a  consideration
in tis development, the focus has been on its usefulness to users and
authors. Having said that I am certainly open to exploring the
possibilities. I had a conversation with one rep from search engine
provider and he indicated that they would consider using it in thier search
algorithm.

Ian wrote:

There are plenty of pages with multiple sections with main content; if we
> did introduce it, it would be once-per-section, not once-per-page.
>

 If you have any good use cases for allowing multiple <main> elements per
page please file a bug agains the spec [2]

[1] http://www.html5accessibility.com/tests/HTML5-main-content/
[2]
https://dvcs.w3.org/hg/html-extensions/raw-file/tip/maincontent/index.html
[3] http://lists.w3.org/Archives/Public/public-html/2012Nov/0129.html
-- 
with regards

Steve Faulkner
Technical Director - TPG

www.paciellogroup.com | www.HTML5accessibility.com |
www.twitter.com/stevefaulkner
HTML5: Techniques for providing useful text alternatives -
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