xref: /original-bsd/usr.bin/pascal/eyacc/eyacc.1 (revision ba762ddc)
1.\" Copyright (c) 1980, 1990 The Regents of the University of California.
2.\" All rights reserved.
3.\"
4.\" %sccs.include.proprietary.man%
5.\"
6.\"	@(#)eyacc.1	6.6 (Berkeley) 04/12/91
7.\"
8.Vx
9.Dd
10.Dt EYACC 1
11.Os BSD 4
12.Sh NAME
13.Nm eyacc
14.Nd modified yacc allowing much improved error recovery
15.Sh SYNOPSIS
16.Nm eyacc
17.Op Fl v
18.Op Ar grammar
19.Sh DESCRIPTION
20.Nm Eyacc
21is an old version of
22.Xr yacc  1  ,
23which produces tables used by the Pascal system and its error recovery
24routines.
25.Nm Eyacc
26fully enumerates test actions in its parser when an error token
27is in the look-ahead set.
28This prevents the parser from making undesirable reductions
29when an error occurs before the error is detected.
30The table format is different in
31.Nm eyacc
32than it was in the old
33.Xr yacc 1 ,
34as minor changes had been made for efficiency reasons.
35.Sh SEE ALSO
36.Xr yacc 1
37.br
38.Em Practical LR Error Recovery
39by Susan L.  Graham, Charles B. Haley and W. N. Joy;
40SIGPLAN Conference on Compiler Construction,
41August 1979.
42.Sh HISTORY
43.Nm Eyacc
44appeared in 4.0 BSD.
45.Sh AUTHORS
46S. C. Johnson
47.br
48.Nm Eyacc
49modifications by Charles Haley and William Joy.
50.Sh BUGS
51.Xr Pc 1
52and its error recovery routines should be made into a library
53of routines for the new
54.Xr yacc 1 .
55