Generalized left-corner parsing

Abstract

We show how techniques known from generalized LR parsing can be applied to left-corner parsing. The resulting parsing algorithm for context-free grammars has some advantages over generalized LR parsing: the sizes and generation times of the parsers are smaller, the produced output is more compact, and the basic parsing technique can more easily be adapted to arbitrary context-free grammes. The algorithm can be seen as an optimization of algorithms known from existing literature. A strong advantage of our presentation is that it makes explicit the role of left-corner posing in these algorithms.