Disambiguation Filters for Scannerless Generalized LR Parsers
Abstract
In this paper we present the fusion of generalized LR parsing and scannerless parsing. This combination supports syntax de.nitions in which all aspects (lexical and context-free) of the syntax of a language are de.ned explicitly in one formalism. Furthermore, there are no restrictions on the class of grammars, thus allowing a natural syntax tree structure. Ambiguities that arise through the use of unrestricted grammars are handled by explicit disambiguation constructs, instead of implicit defaults that are taken by traditional scanner and parser generators. Hence, a syntax de.nition becomes a full declarative description of a language. Scannerless generalized LR parsing is a viable technique that has been applied in various industrial and academic projects.