using markdown in a forum?

[Louis-David Mitterrand]

On Sun, May 02, 2010 at 02:23:28PM +0200, Allan Odgaard wrote:

> On 2 May 2010, at 14:01, Aristotle Pagaltzis wrote:

> 

> >>[...] you want to filter out HTML tags [...]

> >[...] And it's not impossible to write a 100% solid filter if you

> >use a *white*list applied to a real HTML parser.

> 

> Not sure what you mean by "real HTML parser".

> 

> One thing to watch out for is improper HTML when users type a

> literal '<'. I had a lot of users lose part of their comments

> because everything after a standalone '<' was incorrectly filtered.

> 

> This was with WordPress + PHPMarkdown (blog comments). What made it

> worse was that it was the filtered content which went into the

> database, so once filtered, the content was gone.


I'm planning in using HTML::Scrubber (my app is mod_perl).

What would be a "reasonable defaults" whitelist for html tags in a forum
context?

Thanks,