@-commands in raw formatter text

[Karl Berry]

Patrice and I wanted to solicit input on the handling @-commands in raw
blocks.  At its simplest, using HTML as an example (XML and Docbook are
similar):

@html
@@
@end html

The choices are to either interpret such an @ command, so the output is:
@
or not, so that the output is:
@@

Most interesting would be if people actually know of manuals that use
@-commands inside raw blocks, and if so, which commands are there.  As
far as we've seen, @html is mostly used for small fragments of HTML
without any @-commands.

Any thoughts?  Now for the background ...

Existing makeinfo --html does do (some) @-command interpretation inside
raw blocks, like the above, but that is a historical accident rather
than an intentional decision, as far as I can remember.

Clearly commands such as @node and @chapter have no place inside @html.
But it seems to me that the simple text/accent insertion commands, such
as @@ and @'e, could have some value in being able to type them in the
Texinfo way.  At least, there seems to be no harm in it.  It's not like
those Texinfo command sequences are interesting considered as HTML.

The manual says in one place (the Conditionals node) that there is no
interpretation of @-commands, but this was never actually the
implementation, so I don't feel bound by it.  When I added @html @xml
@docbook to the Raw Formatter Commands node, I didn't really think about
it and didn't write anything one way or the other.

Just for completeness on this topic, I'll also state that @tex is always
going to be a different case, because its purpose is to drop "back" into
plain TeX, and there is no equivalent in the other formats.  Due to the
nature of TeX, many @-commands will still work inside @tex (like the
above-mentioned insertions), but others will not due to differences
between plain TeX and Texinfo.

And there has never been raw @info or @plaintext, so that is fine :).

Thanks,
karl