scope ai_groupSimplestNounPhrases_cachedParser.

static Lock #lock = lock();
static AI_BottomUpParser1 #parser;

sS ai_groupSimplestNounPhrases_cachedParser(S s) {
  lock lock;
  if (parser == null)
    parser = ai_standardBUParserWithProductions([[<determiner> + <noun> = <noun>]]);
    
  ret ai_groupUsingProductions(s, parser);
}

end scope