Berkeley Yacc is an LALR(1) parser generator.  Berkeley Yacc has been madeas compatible as possible with AT&T Yacc.  Berkeley Yacc can accept any inputspecification that conforms to the AT&T Yacc documentation.  Specificationsthat take advantage of undocumented features of AT&T Yacc will probably berejected.    Berkeley Yacc is distributed with no warranty whatever.  The code is certainto contain errors.  Neither the author nor any contributor takes responsibilityfor any consequences of its use.    Berkeley Yacc is in the public domain.  The data structures and algorithmsused in Berkeley Yacc are all either taken from documents available to thegeneral public or are inventions of the author.  Anyone may freely distributesource or binary forms of Berkeley Yacc whether unchanged or modified.Distributers may charge whatever fees they can obtain for Berkeley Yacc.Programs generated by Berkeley Yacc may be distributed freely.    Please report bugs to			  corbett@berkeley.eduInclude a small example if possible.  Please include the banner string fromskeleton.c with the bug report.  Do not expect rapid responses.------------------------------------------------------------------------------	ACKNOWLEDGEMENTS	================     Berkeley Yacc owes much to the unflagging efforts of Keith Bostic.His badgering kept me working on it long after I was ready to quit.     Berkeley Yacc is based on the excellent algorithm for computing LALR(1)lookaheads developed by Tom Pennello and Frank DeRemer.  The algorithm isdescribed in their almost impenetrable article in TOPLAS 4,4.     Finally, much of the credit for the latest version must go to thosewho pointed out deficiencies of my earlier releases.  Among the mostprolific contributors were	  Benson I. Margulies	  Dave Gentzel	  Antoine Verheijen	  Peter S. Housel	  Dale Smith	  Ozan Yigit	  John Campbell	  Bill Sommerfeld	  Paul Hilfinger	  Gary Bridgewater	  Dave Bakken	  Dan Lanciani	  Richard Sargent	  Parag Patel------------------------------------------------------------------------------The initial idea for BTYACC came to me after reading the paper	"Parsing Non-LR(k) Grammars with Yacc"	Gary H. Merrill	_Software Prctice and Experience_ Vol. 23(8), 829-850	(August 1993)this paper talks about the basic idea of using a trial parse to resolveconflicts in the grammar.Patches to make things work on MSDOS are courtesy of Pasquale Foggia