That was quite amusing, I read the "Welcome to your new list" message before the wikitech-l message. Anyway, a list just for parser discussion is good. Here's a bit of ANTLR grammar I wrote to handle basic article structure: paragraph blocks and "special blocks", where two consecutive blocks of the same type need an extra linefeed. Since I haven't written any Lex or Yacc before, I'm still wrestling a bit with what are probably fairly basic problems. In this case, I found the requirement of an extra linefeed quite challenging to implement without ambiguity problems. As it is, this does work, but spews out a huge number of warnings and even an apparently non-fatal "fatal error". I presume some of these problems can be avoided through semantic and syntactic predicates, if not backtracking, memoization (no, that's not a typo). Any ANTLR experts here? Steve -- grammar paras; article : pseries? (sseries (EOF| pseries))*; pseries : para (N+ para)* N*; sseries : specialblock (N+ specialblock)* N*; specialblock : (spaceblock|listblock)+; spaceblock : spaceline+; spaceline : SPECIALCHAR char* N; listblock : (listitem)+; listitem: (bulletitem | numberitem | indentitem | defitem); bulletitem : BULLETCHAR (listitem | (nonlistchar char*)? N); numberitem : NUMBERCHAR (listitem | (nonlistchar char*)? N); indentitem : INDENTCHAR (listitem | (nonlistchar char*)? N); defitem : DEFCHAR (nonindentchar)* (definition | INDENTCHAR? N ); definition : ':' char+ N; BULLETCHAR: '*'; NUMBERCHAR: '#'; INDENTCHAR: ':'; DEFCHAR : ';'; para : (nonspecialchar char* N)+; listchar: BULLETCHAR | NUMBERCHAR | INDENTCHAR | DEFCHAR; SPECIALCHAR : ' '; nonlistchar : SPECIALCHAR | nonspecialchar; char : nonlistchar | listchar; nonindentchar : nonlistchar | BULLETCHAR | NUMBERCHAR | DEFCHAR; N : '\r'? '\n' ; nowiki : NOWIKI; NOWIKI : '<nowiki>'( options {greedy=false;} : . )*'</nowiki>'; nonspecialchar : NONSPECIALCHAR | nowiki; NONSPECIALCHAR : ('A'..'Z'| 'a'..'z' | '0'..'9' | '\'' | '"' | '(' | ')')+; -- PS you might notice the above grammar implements two "improvements" to the ;definition:term notation: 1. The ;definition has to be the last item in the list. Constructs like ##;## are worthless. 2. A trailing : is treated literally.