[whatwg] Footnotes, endnotes, sidenotes

[James Graham]

Michel Fortin wrote:
> Le 30 oct. 2006 à 15:33, Ian Hickson a écrit :

>> One thing to consider when
>> looking at footnotes is "would the title="" attribute handle this use 
>> case
>> as well as what I'm proposing?". If the answer is "yes", or "almost", 
>> then
>> it's probably not a good idea to introduce the new feature.
> 
> Would the title attribute be suffisent? I don't think so. The main 
> problem being that an attribute cannot contain any markup (links, 
> emphasis, paragraphs?).

+1

> I'm all for a syntax for footnotes (and sidenotes, and endnotes).

I think and distinction between footnotes, sidenotes and endnotes is basically 
presentational and whilst we should try to ensure that markup+CSS can create all 
three appearances we shouldn't treat them distinctly.

> 1. One of them, mostly used with sidenotes, is to have the note directly 
> in the text:
> 
>     <p>Some text <span class="sidenote">this is a sidenote to put
>        in the margin</span> and some other text.</p>

This seems to have a poor backward compatibility story - in a non-supporting UA 
the note ends up in the flow.

> 2. Some syntaxes meant to be written directly by humans, like Latex, 

(we should consider HTML to be such a language)

> also allow you to defer the note content until a later time to make 
> things more readable. In these cases, you put a marker in the text, then 
> associate the marker with the note content which can be placed elsewhere 
> in the document. This make the text more readable. My own text-to-HTML 
> tool (PHP Markdown Extra, semi-private beta version 1.1) use such a syntax:
> 
>     Paragraph linked to a footnote[^1].
> 
>     [^1]: This is the footnote content.
> 
>     Some other paragraph.
> 
> I'm not aware of anyone doing this for footnotes or sidenotes in HTML; 
> it doesn't seem very practical to style either.

This seems structurally rather similar to case 3 (below) albeit with a non-HTML 
syntax.

> 3. The last method of expressing footnotes in HTML is to create markers 
> in the text and put the footnotes in an ordered list at the bottom of 
> the page. For instance, my text-to-HTML tool generates this markup from 
> the above example:
> 
>     <p>Paragraph linked to a footnote
>        <sup><a id="fnref:1" href="#fn:1" rel="footnote">1</a></sup>.
>     </p>
> 
>     <p>Some other paragraph</p>
> 
>     <div class="footnotes">
>     <hr />
> 
>     <ol>
>     <li id="fn:1">
>        <p>This is the footnote content.
>           <a href="#fnref:1" rev="footnote">↩</a>
>        </p>
>     </li>
>     </ol>
>     </div>
> 
> This provides a trivial way to style footnotes as footnote, it'll even 
> looks good unstyled and is completely backward compatible.

Indeed. +1 on this general idea -1 on the precise markup, in particular the 
<div><ol> structure for the list of notes (this should be a new element, if 
possible) and the use of <sup>. It would also be nice to reduce some of the 
excess baggage on the <a> element, if possible.


> Before defining a markup for footnotes or sidenotes, I think it'd be a 
> good idea to see what goals the syntax should fulfill. Is backward 
> compatibility one of them, or should we always rely on the browser 
> capabilities to relocate footnotes where they should be, or should we 
> allow both?

Both. For example in paged media the footnote should typically be placed at the 
end of the current page, whereas on-screen, the end of the section is usually 
more appropriate.

> *   Footnotes should probably not be allowed to escape their enclosing 
> article element. For instance, if you have a couple of weblog articles 
> on your main page, each article having some footnotes, it'd probably not 
> be a good idea to have footnotes from all articles mixed together in the 
> same list.

Yes, the positioning and counters should be tied to the enclosing sectional element.

> *   Although not necessarily very common, some people like to put 
> multiple paragraphs, lists, and some other block-level elements in 
> footnotes and sidenotes (more often seen in sidenotes in books). I think 
> it'd be a good idea to allow that in the markup.

+1

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