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Bison supports both traditional single-letter options and mnemonic long option names. Long option names are indicated with ‘--’ instead of ‘-’. Abbreviations for option names are allowed as long as they are unique. When a long option takes an argument, like ‘--file-prefix’, connect the option name and the argument with ‘=’.
Here is a list of options that can be used with Bison, alphabetized by short option. It is followed by a cross key alphabetized by long option.
Operations modes:
#define
statements in addition to an enum
to associate token numbers with token
names.
Thus, the following shell script can substitute for Yacc, and the Bison
distribution contains such a script for compatibility with POSIX:
#! /bin/sh bison -y "$@"
The -y/--yacc option is intended for use with
traditional Yacc grammars. If your grammar uses a Bison extension
like ‘%glr-parser’, Bison might not be Yacc-compatible even if
this option is specified.
midrule-values
$2
in:
exp: '1' { $$ = 1; } '+' exp { $$ = $1 + $4; };
Also warn about mid-rule values that are used but not set.
For example, warn about unset $$
in the mid-rule action in:
exp: '1' { $1 = 1; } '+' exp { $$ = $2 + $4; };
These warnings are not enabled by default since they sometimes prove to
be false alarms in existing grammars employing the Yacc constructs
$0
or $-
n (where n is some positive integer).
yacc
all
none
error
A category can be turned off by prefixing its name with ‘no-’. For instance, -Wno-syntax will hide the warnings about unused variables.
Tuning the parser:
YYDEBUG
to 1 if it is not
already defined, so that the debugging facilities are compiled.
See Tracing Your Parser.
%language
was specified (see Bison Declaration Summary). Currently supported languages include C, C++, and Java.
language is case-insensitive.
This option is experimental and its effect may be modified in future
releases.
%locations
was specified. See Decl Summary.
%name-prefix "
prefix"
was specified.
See Decl Summary.
#line
preprocessor commands in the parser file.
Ordinarily Bison puts them in the parser file so that the C compiler
and debuggers will associate errors with your source file, the
grammar file. This option causes them to associate errors with the
parser file, treating it as an independent source file in its own right.
%skeleton
(see Bison Declaration Summary).
If file does not contain a /
, file is the name of a skeleton
file in the Bison installation directory.
If it does, file is an absolute file name or a file name relative to the
current working directory.
This is similar to how most shells resolve commands.
%token-table
was specified. See Decl Summary.
Adjust the output:
%defines
was specified, i.e., write an extra output
file containing macro definitions for the token type names defined in
the grammar, as well as a few other declarations. See Decl Summary.
--defines
except -d
does not accept a
file argument since POSIX Yacc requires that -d
can be bundled
with other short options.
%file-prefix
was specified, i.e., specify prefix to use
for all Bison output file names. See Decl Summary.
state
lookahead
state
and augments the description of the automaton with
each rule's lookahead set.
itemset
state
and augments the description of the automaton with
the full set of items for each state, instead of its core only.
%verbose
was specified, i.e., write an extra output
file containing verbose descriptions of the grammar and
parser. See Decl Summary.
The other output files' names are constructed from file as
described under the ‘-v’ and ‘-d’ options.