Unrestricted Gapping Grammars

Since the introduction of metamorphosis grammars (MGs) 'Colmerauer. 1978). with their associated type 0-like grammar rules, there has been a desire to allow more general rule formats in logic grammars Gaps, which refer to strings of unspecified symbols, were added to the MG rule, resulting in extraposition grammars (XGs) (Pereira, 1981) and gapping grammars (GGs) (Dahl and Abramson, 1984). Unrestricted gapping grammars, which provide an even more general rule format, possess rules of the form "a > B" where a and /3 many contain any number of terminal nonterminal or gap symbols in any order. FIGG. a Flexible Implementation of Gapping Grammars, is an implementation of a large subset of unrestricted GGs which allows either bottom-up or top-down parsing of sentences. This system provides more built in control facilities than previous logic grammar implementations, which allows the user to restrict the applicability of the rules, and to create grammar rules that will be executed more efficiently