1.\" Copyright (c) 1980, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)eyacc.1 6.5 (Berkeley) 03/14/91 7.\" 8.Vx 9.Vx 10.Dd 11.Dt EYACC 1 12.Os BSD 4 13.Sh NAME 14.Nm eyacc 15.Nd modified yacc allowing much improved error recovery 16.Sh SYNOPSIS 17.Nm eyacc 18.Op Fl v 19.Op Ar grammar 20.Sh DESCRIPTION 21.Nm Eyacc 22is an old version of 23.Xr yacc 1 , 24which produces tables used by the Pascal system and its error recovery 25routines. 26.Nm Eyacc 27fully enumerates test actions in its parser when an error token 28is in the look-ahead set. 29This prevents the parser from making undesirable reductions 30when an error occurs before the error is detected. 31The table format is different in 32.Nm eyacc 33than it was in the old 34.Xr yacc 1 , 35as minor changes had been made for efficiency reasons. 36.Sh SEE ALSO 37.Xr yacc 1 38.br 39.Em Practical LR Error Recovery 40by Susan L. Graham, Charles B. Haley and W. N. Joy; 41SIGPLAN Conference on Compiler Construction, 42August 1979. 43.Sh HISTORY 44.Nm Eyacc 45appeared in 4.0 BSD. 46.Sh AUTHORS 47S. C. Johnson 48.br 49.Nm Eyacc 50modifications by Charles Haley and William Joy. 51.Sh BUGS 52.Xr Pc 1 53and its error recovery routines should be made into a library 54of routines for the new 55.Xr yacc 1 . 56