inference div10 Nals rule schema Felucca element parser nonterminal sequent polyadenylation parse XPath syntactic Laserburn Tefkat superko IUPAC disapplied NWN2 SECIS photoabsorption HTML Kriegspiel samaneras instantiation predicates mutable rewriting RuleML BattleForce XML nested Patimokkha Szybalski Sousai simple