Generalized LR parsing and the shuffle operator
  We adapt Tomita's Generalized LR algorithm to languages generated by context-free grammars enriched with a shuffle operator. The change involves extensions to the underlying handle-finding finite automaton, construction of parser tables, and the necessary optimizations in constructing a deterministic parser. Our system is motivated by an application from artificial intelligence plan recognition. We argue for the correctness of the system, and discuss future extensions of this work. 
John Maraist
cs.FL