manpage

伯克利的语法分析器的创建工具

.\"	%W%	%R% (Berkeley) %E%
.\"
.TH YACC 1 "December 10, 1989"
.UC 6
.SH NAME
Yacc \- an LALR(1) parser generator
.SH SYNOPSIS
.B yacc [ -dltv ] [ -b
.I prefix
.B ]
.I filename
.SH DESCRIPTION
.I Yacc
reads the grammar specification in the file
.I filename
and generates an LR(1) parser for it.
The parsers consist of a set of LALR(1) parsing tables and a driver routine
written in the C programming language.
.I Yacc
normally writes the parse tables and the driver routine to the file
.IR y.tab.c.
.PP
The following options are available:
.RS
.TP
\fB-b \fIprefix\fR
The
.B -b
option changes the prefix prepended to the output file names to
the string denoted by
.IR prefix.
The default prefix is the character
.IR y.
.TP
.B -d
The \fB-d\fR option causes the header file
.IR y.tab.h
to be written.
.TP
.B -l
If the
.B -l
option is not specified,
.I yacc
will insert \#line directives in the generated code.
The \#line directives let the C compiler relate errors in the
generated code to the user's original code.
If the \fB-l\fR option is specified,
.I yacc
will not insert the \#line directives.
\&\#line directives specified by the user will be retained.
.TP
.B -t
The
.B -t
option will change the preprocessor directives generated by
.I yacc
so that debugging statements will be incorporated in the compiled code.
.TP
.B -v
The
.B -v
option causes a human-readable description of the generated parser to
be written to the file
.IR y.output.
.RE
.PP
If the environment variable TMPDIR is set, the string denoted by
TMPDIR will be used as the name of the directory where the temporary
files are created.
.SH TABLES
There is a program \fI:yyfix\fR
that extracts tables from \fIyacc\fR-generated
files.
The program takes the names of the tables as its command-line arguments.
The names of the tables generated by this version of
.I yacc
are
.IR yylhs,
.IR yylen,
.IR yydefred,
.IR yydgoto,
.IR yysindex,
.IR yyrindex,
.IR yygindex,
.IR yytable,
and
.IR yycheck.
Two additional tables,
.I yyname
and
.I yyrule,
are created if YYDEBUG is defined and nonzero.
.SH FILES
.IR y.tab.c
.br
.IR y.tab.h
.br
.IR y.output
.br
.IR /tmp/yacc.aXXXXXX
.br
.IR /tmp/yacc.tXXXXXX
.br
.IR /tmp/yacc.uXXXXXX
.SH DIAGNOSTICS
If there are rules that are never reduced, the number of such rules is
reported on standard error.
If there are any LALR(1) conflicts, the number of conflicts is reported
on standard error.