On Sun, Sep 20, 2009 at 8:14 PM, Tim Starling <[email protected]> wrote: > Robert Rohde wrote: >> I am looking at bug 1310, which involves parser behavior such that >> when given nested tag extensions, i.e.: >> >> <tag> >> AAA >> <tag>BBB</tag> >> CCC >> </tag> >> >> The parser selects the tag block as running from the first open tag to >> the FIRST close tag, i.e. in the example it gives: >> >> AAA >> <tag>BBB >> >> as the inner text of the first tag. It should be fairly >> straightforward to modify this to handle nested tags by checking for >> additional open tags in the inner string. > > This syntax was chosen because originally <pre> and <nowiki> were the > only such tags (I called them xmlish elements in [[mw:Preprocessor > ABNF]]). Those two tags were imagined as being useful solely for > escaping HTML and other wikitext, so that it is displayed literally on > the page. No nesting behaviour was desirable.
Actually, if one is following the HTML4 spec then <pre> would be expected to nest. (Not particularly useful as far as I can see, but it is what it is.) I could see arguments in either direction for nowiki. For example, it might be nice to be able to wrap <nowiki> around arbitrary blocks without worrying if another nowiki was already present in the middle. > <math>, and then the extension interface, were added afterwards using > the same syntax. There is no application for nesting with <math> since > the contents are TeX. > > <ref> was the first tag to assume that its contents were some kind of > wikitext, unfortunately this was an inefficient and ugly hack on the > software side, and could have been much more easily done, with > appropriate nesting behaviour, if a different syntax had been chosen. > Other tags were later added, following this bad example. > > So if you ask me if there's a use case, I would say most likely yes, > especially for <nowiki> and <pre>, and very likely for the extensions > that shell out, like <math> and <lilypond>. These use cases would > become especially obvious if an extension registered a short name name > like <->, then the lack of a syntax for communicating this string with > a shell command would become especially obvious. I can't really think of an example where it would be valid and useful to enclose a single tag, i.e. <math> x + <math> 5 = 6 </math> is silly, but I can't rule out that there might be some circumstance somewhere where one would want that behavior. > But it would be possible to enable or disable nesting on a per-tag > basis at registration time. That seems like probably the best option. -Robert Rohde _______________________________________________ Wikitech-l mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikitech-l
