Bad regular expressions in parser.php

While looking into the latest beta version of FluxBB (1.4), I did some analysis of the parser (version 1078 - which is a variation of PunBB/FLuxBB 1.3). Well as it turns out the first two regular expressions both have errors! I wrote an in-depth article which describes these two regexes in detail (and their problems), and provides improved versions (which solve the problems). Although this article was originally written to target the FluxBB 1.4 parser.php, the exact same problems exist in PunBB 1.3.4. The only difference is the line numbers on which they occur. I have updated the article to include the affected line numbers for the PunBB 1.3.4 parser.

Here is a link to my article: FluxBB Parser Regular Expressions

(Caution: this is something only a true regex-geek would love!)

Note that the negative effects of these regex errors are minor - the only effect that users will see is that nested lists do not work correctly when the nested list has no '1', 'a' or '*' attribute specified. (i.e. you can nest using the {list=1} or {list=*} syntax, but you cannot nest the simple, attribute-free {list} syntax.)