Extending lookahead for LR parsers

LR Parsers For Natural Languages

MLR, an extended LR parser, is introduced, and its application to natural language parsing is discussed. An LR parser is a ~;hift-reduce parser which is doterministically guided by a parsing table. A parsing table can be obtained automatically from a context-free phrase structure grammar. LR parsers cannot manage antl)iguous grammars such as natural language grammars, because their I)arsing tab...

Validating LR(1) Parsers

An LR(1) parser is a finite-state automaton, equipped with a stack, which uses a combination of its current state and one lookahead symbol in order to determine which action to perform next. We present a validator which, when applied to a context-free grammar G and an automaton A, checks that A and G agree. Validating the parser provides the correctness guarantees required by verified compilers...

A unifying model for lookahead LR parsing

Incremental Generation of LR Parsers

Implementation of a new compiler usually requires making frequent adjustments to grammar de nitions. An incremental technique for updating the parser tables after a minor change to the grammar could potentially save much computational e ort. More importantly, debugging a grammar is made easier if the grammar is re-checked for correctness after each small change to the grammar. The basic design ...

Error Recovery in LR Parsers

This report presents a survey of four syntax error recovery techniques for LR Parsers. The techniques presented are described in [Modry 78, Graham 79, Sippu 83, Mckenzie 95, Bertsch 99]. After an introduction to general syntactic error recovery techniques in LR parsers, I would present a brief overview and comparison of these techniques in this report.