X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/eb0e86ac80861525ab5d0c0dcb585290e1bd3f03..8a4ec3595b706180f53458607cd64cca07af24cb:/doc/bison.texi?ds=sidebyside diff --git a/doc/bison.texi b/doc/bison.texi index 1351a6c1..d4022159 100644 --- a/doc/bison.texi +++ b/doc/bison.texi @@ -1,6 +1,8 @@ \input texinfo @c -*-texinfo-*- @comment %**start of header @setfilename bison.info +@documentencoding UTF-8 +@documentlanguage en @include version.texi @settitle Bison @value{VERSION} @setchapternewpage odd @@ -33,7 +35,7 @@ This manual (@value{UPDATED}) is for GNU Bison (version @value{VERSION}), the GNU parser generator. -Copyright @copyright{} 1988-1993, 1995, 1998-2013 Free Software +Copyright @copyright{} 1988-1993, 1995, 1998-2015 Free Software Foundation, Inc. @quotation @@ -211,6 +213,9 @@ Defining Language Semantics * Value Type:: Specifying one data type for all semantic values. * Multiple Types:: Specifying several alternative data types. +* Type Generation:: Generating the semantic value type. +* Union Decl:: Declaring the set of all semantic value types. +* Structured Value Type:: Providing a structured semantic value type. * Actions:: An action is the semantic definition of a grammar rule. * Action Types:: Specifying data types for actions to operate on. * Mid-Rule Actions:: Most actions go at the end of a rule. @@ -234,7 +239,6 @@ Bison Declarations * Require Decl:: Requiring a Bison version. * Token Decl:: Declaring terminal symbols. * Precedence Decl:: Declaring terminals with precedence and associativity. -* Union Decl:: Declaring the set of all semantic value types. * Type Decl:: Declaring the choice of type for a nonterminal symbol. * Initial Action Decl:: Code run before parsing starts. * Destructor Decl:: Declaring how symbols are freed. @@ -364,6 +368,7 @@ Java Parsers * Java Parser Interface:: Instantiating and running the parser * Java Scanner Interface:: Specifying the scanner for the parser * Java Action Features:: Special features for use in actions +* Java Push Parser Interface:: Instantiating and running the a push parser * Java Differences:: Differences between C/C++ and Java Grammars * Java Declarations Summary:: List of Bison declarations used with Java @@ -1546,7 +1551,6 @@ calculator. As in C, comments are placed between @samp{/*@dots{}*/}. @group %@{ - #define YYSTYPE double #include #include int yylex (void); @@ -1554,6 +1558,7 @@ calculator. As in C, comments are placed between @samp{/*@dots{}*/}. %@} @end group +%define api.value.type @{double@} %token NUM %% /* Grammar rules and actions follow. */ @@ -1562,14 +1567,6 @@ calculator. As in C, comments are placed between @samp{/*@dots{}*/}. The declarations section (@pxref{Prologue, , The prologue}) contains two preprocessor directives and two forward declarations. -The @code{#define} directive defines the macro @code{YYSTYPE}, thus -specifying the C data type for semantic values of both tokens and -groupings (@pxref{Value Type, ,Data Types of Semantic Values}). The -Bison parser will use whatever type @code{YYSTYPE} is defined as; if you -don't define it, @code{int} is the default. Because we specify -@code{double}, each token and each expression has an associated value, -which is a floating point number. - The @code{#include} directive is used to declare the exponentiation function @code{pow}. @@ -1579,14 +1576,24 @@ before they are used. These functions will be defined in the epilogue, but the parser calls them so they must be declared in the prologue. -The second section, Bison declarations, provides information to Bison -about the token types (@pxref{Bison Declarations, ,The Bison -Declarations Section}). Each terminal symbol that is not a -single-character literal must be declared here. (Single-character -literals normally don't need to be declared.) In this example, all the -arithmetic operators are designated by single-character literals, so the -only terminal symbol that needs to be declared is @code{NUM}, the token -type for numeric constants. +The second section, Bison declarations, provides information to Bison about +the tokens and their types (@pxref{Bison Declarations, ,The Bison +Declarations Section}). + +The @code{%define} directive defines the variable @code{api.value.type}, +thus specifying the C data type for semantic values of both tokens and +groupings (@pxref{Value Type, ,Data Types of Semantic Values}). The Bison +parser will use whatever type @code{api.value.type} is defined as; if you +don't define it, @code{int} is the default. Because we specify +@samp{@{double@}}, each token and each expression has an associated value, +which is a floating point number. C code can use @code{YYSTYPE} to refer to +the value @code{api.value.type}. + +Each terminal symbol that is not a single-character literal must be +declared. (Single-character literals normally don't need to be declared.) +In this example, all the arithmetic operators are designated by +single-character literals, so the only terminal symbol that needs to be +declared is @code{NUM}, the token type for numeric constants. @node Rpcalc Rules @subsection Grammar Rules for @code{rpcalc} @@ -1800,9 +1807,9 @@ therefore, @code{NUM} becomes a macro for @code{yylex} to use. The semantic value of the token (if it has one) is stored into the global variable @code{yylval}, which is where the Bison parser will look -for it. (The C data type of @code{yylval} is @code{YYSTYPE}, which was -defined at the beginning of the grammar; @pxref{Rpcalc Declarations, -,Declarations for @code{rpcalc}}.) +for it. (The C data type of @code{yylval} is @code{YYSTYPE}, whose value +was defined at the beginning of the grammar via @samp{%define api.value.type +@{double@}}; @pxref{Rpcalc Declarations,,Declarations for @code{rpcalc}}.) A token type code of zero is returned if the end-of-input is encountered. (Bison recognizes any nonpositive value as indicating end-of-input.) @@ -1991,7 +1998,6 @@ parentheses nested to arbitrary depth. Here is the Bison code for @group %@{ - #define YYSTYPE double #include #include int yylex (void); @@ -2001,6 +2007,7 @@ parentheses nested to arbitrary depth. Here is the Bison code for @group /* Bison declarations. */ +%define api.value.type @{double@} %token NUM %left '-' '+' %left '*' '/' @@ -2150,13 +2157,13 @@ the same as the declarations for the infix notation calculator. /* Location tracking calculator. */ %@{ - #define YYSTYPE int #include int yylex (void); void yyerror (char const *); %@} /* Bison declarations. */ +%define api.value.type @{int@} %token NUM %left '-' '+' @@ -2409,15 +2416,10 @@ Here are the C and Bison declarations for the multi-function calculator. %@} @end group -@group -%union @{ - double val; /* For returning numbers. */ - symrec *tptr; /* For returning symbol-table pointers. */ -@} -@end group -%token NUM /* Simple double precision number. */ -%token VAR FNCT /* Variable and function. */ -%type exp +%define api.value.type union /* Generate YYSTYPE from these types: */ +%token NUM /* Simple double precision number. */ +%token VAR FNCT /* Symbol table pointer: variable and function. */ +%type exp @group %precedence '=' @@ -2432,23 +2434,23 @@ The above grammar introduces only two new features of the Bison language. These features allow semantic values to have various data types (@pxref{Multiple Types, ,More Than One Value Type}). -The @code{%union} declaration specifies the entire list of possible types; -this is instead of defining @code{YYSTYPE}. The allowable types are now -double-floats (for @code{exp} and @code{NUM}) and pointers to entries in -the symbol table. @xref{Union Decl, ,The Collection of Value Types}. - -Since values can now have various types, it is necessary to associate a -type with each grammar symbol whose semantic value is used. These symbols -are @code{NUM}, @code{VAR}, @code{FNCT}, and @code{exp}. Their -declarations are augmented with information about their data type (placed -between angle brackets). - -The Bison construct @code{%type} is used for declaring nonterminal -symbols, just as @code{%token} is used for declaring token types. We -have not used @code{%type} before because nonterminal symbols are -normally declared implicitly by the rules that define them. But -@code{exp} must be declared explicitly so we can specify its value type. -@xref{Type Decl, ,Nonterminal Symbols}. +The special @code{union} value assigned to the @code{%define} variable +@code{api.value.type} specifies that the symbols are defined with their data +types. Bison will generate an appropriate definition of @code{YYSTYPE} to +store these values. + +Since values can now have various types, it is necessary to associate a type +with each grammar symbol whose semantic value is used. These symbols are +@code{NUM}, @code{VAR}, @code{FNCT}, and @code{exp}. Their declarations are +augmented with their data type (placed between angle brackets). For +instance, values of @code{NUM} are stored in @code{double}. + +The Bison construct @code{%type} is used for declaring nonterminal symbols, +just as @code{%token} is used for declaring token types. Previously we did +not use @code{%type} before because nonterminal symbols are normally +declared implicitly by the rules that define them. But @code{exp} must be +declared explicitly so we can specify its value type. @xref{Type Decl, +,Nonterminal Symbols}. @node Mfcalc Rules @subsection Grammar Rules for @code{mfcalc} @@ -2672,11 +2674,18 @@ yylex (void) if (c == '.' || isdigit (c)) @{ ungetc (c, stdin); - scanf ("%lf", &yylval.val); + scanf ("%lf", &yylval.NUM); return NUM; @} @end group +@end example + +@noindent +Bison generated a definition of @code{YYSTYPE} with a member named +@code{NUM} to store value of @code{NUM} symbols. +@comment file: mfcalc.y: 3 +@example @group /* Char starts an identifier => read the name. */ if (isalpha (c)) @@ -2718,7 +2727,7 @@ yylex (void) s = getsym (symbuf); if (s == 0) s = putsym (symbuf, VAR); - yylval.tptr = s; + *((symrec**) &yylval) = s; return s->type; @} @@ -3636,6 +3645,9 @@ the numbers associated with @var{x} and @var{y}. @menu * Value Type:: Specifying one data type for all semantic values. * Multiple Types:: Specifying several alternative data types. +* Type Generation:: Generating the semantic value type. +* Union Decl:: Declaring the set of all semantic value types. +* Structured Value Type:: Providing a structured semantic value type. * Actions:: An action is the semantic definition of a grammar rule. * Action Types:: Specifying data types for actions to operate on. * Mid-Rule Actions:: Most actions go at the end of a rule. @@ -3657,17 +3669,38 @@ Notation Calculator}). Bison normally uses the type @code{int} for semantic values if your program uses the same data type for all language constructs. To -specify some other type, define @code{YYSTYPE} as a macro, like this: +specify some other type, define the @code{%define} variable +@code{api.value.type} like this: + +@example +%define api.value.type @{double@} +@end example + +@noindent +or + +@example +%define api.value.type @{struct semantic_type@} +@end example + +The value of @code{api.value.type} should be a type name that does not +contain parentheses or square brackets. + +Alternatively, instead of relying of Bison's @code{%define} support, you may +rely on the C/C++ preprocessor and define @code{YYSTYPE} as a macro, like +this: @example #define YYSTYPE double @end example @noindent -@code{YYSTYPE}'s replacement list should be a type name -that does not contain parentheses or square brackets. This macro definition must go in the prologue of the grammar file -(@pxref{Grammar Outline, ,Outline of a Bison Grammar}). +(@pxref{Grammar Outline, ,Outline of a Bison Grammar}). If compatibility +with POSIX Yacc matters to you, use this. Note however that Bison cannot +know @code{YYSTYPE}'s value, not even whether it is defined, so there are +services it cannot provide. Besides this works only for languages that have +a preprocessor. @node Multiple Types @subsection More Than One Value Type @@ -3683,11 +3716,25 @@ requires you to do two things: @itemize @bullet @item -Specify the entire collection of possible data types, either by using the -@code{%union} Bison declaration (@pxref{Union Decl, ,The Collection of -Value Types}), or by using a @code{typedef} or a @code{#define} to -define @code{YYSTYPE} to be a union type whose member names are -the type tags. +Specify the entire collection of possible data types. There are several +options: +@itemize @bullet +@item +let Bison compute the union type from the tags you assign to symbols; + +@item +use the @code{%union} Bison declaration (@pxref{Union Decl, ,The Union +Declaration}); + +@item +define the @code{%define} variable @code{api.value.type} to be a union type +whose members are the type tags (@pxref{Structured Value Type,, Providing a +Structured Semantic Value Type}); + +@item +use a @code{typedef} or a @code{#define} to define @code{YYSTYPE} to be a +union type whose member names are the type tags. +@end itemize @item Choose one of those types for each symbol (terminal or nonterminal) for @@ -3697,6 +3744,164 @@ and for groupings with the @code{%type} Bison declaration (@pxref{Type Decl, ,Nonterminal Symbols}). @end itemize +@node Type Generation +@subsection Generating the Semantic Value Type +@cindex declaring value types +@cindex value types, declaring +@findex %define api.value.type union + +The special value @code{union} of the @code{%define} variable +@code{api.value.type} instructs Bison that the tags used with the +@code{%token} and @code{%type} directives are genuine types, not names of +members of @code{YYSTYPE}. + +For example: + +@example +%define api.value.type union +%token INT "integer" +%token 'n' +%type expr +%token ID "identifier" +@end example + +@noindent +generates an appropriate value of @code{YYSTYPE} to support each symbol +type. The name of the member of @code{YYSTYPE} for tokens than have a +declared identifier @var{id} (such as @code{INT} and @code{ID} above, but +not @code{'n'}) is @code{@var{id}}. The other symbols have unspecified +names on which you should not depend; instead, relying on C casts to access +the semantic value with the appropriate type: + +@example +/* For an "integer". */ +yylval.INT = 42; +return INT; + +/* For an 'n', also declared as int. */ +*((int*)&yylval) = 42; +return 'n'; + +/* For an "identifier". */ +yylval.ID = "42"; +return ID; +@end example + +If the @code{%define} variable @code{api.token.prefix} is defined +(@pxref{%define Summary,,api.token.prefix}), then it is also used to prefix +the union member names. For instance, with @samp{%define api.token.prefix +@{TOK_@}}: + +@example +/* For an "integer". */ +yylval.TOK_INT = 42; +return TOK_INT; +@end example + +This Bison extension cannot work if @code{%yacc} (or +@option{-y}/@option{--yacc}) is enabled, as POSIX mandates that Yacc +generate tokens as macros (e.g., @samp{#define INT 258}, or @samp{#define +TOK_INT 258}). + +This feature is new, and user feedback would be most welcome. + +A similar feature is provided for C++ that in addition overcomes C++ +limitations (that forbid non-trivial objects to be part of a @code{union}): +@samp{%define api.value.type variant}, see @ref{C++ Variants}. + +@node Union Decl +@subsection The Union Declaration +@cindex declaring value types +@cindex value types, declaring +@findex %union + +The @code{%union} declaration specifies the entire collection of possible +data types for semantic values. The keyword @code{%union} is followed by +braced code containing the same thing that goes inside a @code{union} in C@. + +For example: + +@example +@group +%union @{ + double val; + symrec *tptr; +@} +@end group +@end example + +@noindent +This says that the two alternative types are @code{double} and @code{symrec +*}. They are given names @code{val} and @code{tptr}; these names are used +in the @code{%token} and @code{%type} declarations to pick one of the types +for a terminal or nonterminal symbol (@pxref{Type Decl, ,Nonterminal Symbols}). + +As an extension to POSIX, a tag is allowed after the @code{%union}. For +example: + +@example +@group +%union value @{ + double val; + symrec *tptr; +@} +@end group +@end example + +@noindent +specifies the union tag @code{value}, so the corresponding C type is +@code{union value}. If you do not specify a tag, it defaults to +@code{YYSTYPE} (@pxref{%define Summary,,api.value.union.name}). + +As another extension to POSIX, you may specify multiple @code{%union} +declarations; their contents are concatenated. However, only the first +@code{%union} declaration can specify a tag. + +Note that, unlike making a @code{union} declaration in C, you need not write +a semicolon after the closing brace. + +@node Structured Value Type +@subsection Providing a Structured Semantic Value Type +@cindex declaring value types +@cindex value types, declaring +@findex %union + +Instead of @code{%union}, you can define and use your own union type +@code{YYSTYPE} if your grammar contains at least one @samp{<@var{type}>} +tag. For example, you can put the following into a header file +@file{parser.h}: + +@example +@group +union YYSTYPE @{ + double val; + symrec *tptr; +@}; +@end group +@end example + +@noindent +and then your grammar can use the following instead of @code{%union}: + +@example +@group +%@{ +#include "parser.h" +%@} +%define api.value.type @{union YYSTYPE@} +%type expr +%token ID +@end group +@end example + +Actually, you may also provide a @code{struct} rather that a @code{union}, +which may be handy if you want to track information for every symbol (such +as preceding comments). + +The type you provide may even be structured and include pointers, in which +case the type tags you provide may be composite, with @samp{.} and @samp{->} +operators. + @node Actions @subsection Actions @cindex action @@ -4262,8 +4467,7 @@ exp: else @{ $$ = 1; - fprintf (stderr, - "Division by zero, l%d,c%d-l%d,c%d", + fprintf (stderr, "%d.%d-%d.%d: division by zero", @@3.first_line, @@3.first_column, @@3.last_line, @@3.last_column); @} @@ -4290,8 +4494,7 @@ exp: else @{ $$ = 1; - fprintf (stderr, - "Division by zero, l%d,c%d-l%d,c%d", + fprintf (stderr, "%d.%d-%d.%d: division by zero", @@3.first_line, @@3.first_column, @@3.last_line, @@3.last_column); @} @@ -4499,7 +4702,6 @@ and Context-Free Grammars}). * Require Decl:: Requiring a Bison version. * Token Decl:: Declaring terminal symbols. * Precedence Decl:: Declaring terminals with precedence and associativity. -* Union Decl:: Declaring the set of all semantic value types. * Type Decl:: Declaring the choice of type for a nonterminal symbol. * Initial Action Decl:: Code run before parsing starts. * Destructor Decl:: Declaring how symbols are freed. @@ -4682,87 +4884,6 @@ For example: %left OR 134 "<=" 135 // Declares 134 for OR and 135 for "<=". @end example -@node Union Decl -@subsection The Collection of Value Types -@cindex declaring value types -@cindex value types, declaring -@findex %union - -The @code{%union} declaration specifies the entire collection of -possible data types for semantic values. The keyword @code{%union} is -followed by braced code containing the same thing that goes inside a -@code{union} in C@. - -For example: - -@example -@group -%union @{ - double val; - symrec *tptr; -@} -@end group -@end example - -@noindent -This says that the two alternative types are @code{double} and @code{symrec -*}. They are given names @code{val} and @code{tptr}; these names are used -in the @code{%token} and @code{%type} declarations to pick one of the types -for a terminal or nonterminal symbol (@pxref{Type Decl, ,Nonterminal Symbols}). - -As an extension to POSIX, a tag is allowed after the -@code{union}. For example: - -@example -@group -%union value @{ - double val; - symrec *tptr; -@} -@end group -@end example - -@noindent -specifies the union tag @code{value}, so the corresponding C type is -@code{union value}. If you do not specify a tag, it defaults to -@code{YYSTYPE}. - -As another extension to POSIX, you may specify multiple -@code{%union} declarations; their contents are concatenated. However, -only the first @code{%union} declaration can specify a tag. - -Note that, unlike making a @code{union} declaration in C, you need not write -a semicolon after the closing brace. - -Instead of @code{%union}, you can define and use your own union type -@code{YYSTYPE} if your grammar contains at least one -@samp{<@var{type}>} tag. For example, you can put the following into -a header file @file{parser.h}: - -@example -@group -union YYSTYPE @{ - double val; - symrec *tptr; -@}; -typedef union YYSTYPE YYSTYPE; -@end group -@end example - -@noindent -and then your grammar can use the following -instead of @code{%union}: - -@example -@group -%@{ -#include "parser.h" -%@} -%type expr -%token ID -@end group -@end example - @node Type Decl @subsection Nonterminal Symbols @cindex declaring value types, nonterminals @@ -4781,7 +4902,7 @@ used. This is done with a @code{%type} declaration, like this: @noindent Here @var{nonterminal} is the name of a nonterminal symbol, and @var{type} is the name given in the @code{%union} to the alternative -that you want (@pxref{Union Decl, ,The Collection of Value Types}). You +that you want (@pxref{Union Decl, ,The Union Declaration}). You can give any number of nonterminal symbols in the same @code{%type} declaration, if they have the same value type. Use spaces to separate the symbol names. @@ -4877,10 +4998,8 @@ For example: @example %union @{ char *string; @} -%token STRING1 -%token STRING2 -%type string1 -%type string2 +%token STRING1 STRING2 +%type string1 string2 %union @{ char character; @} %token CHR %type chr @@ -5006,10 +5125,8 @@ For example: @example %union @{ char *string; @} -%token STRING1 -%token STRING2 -%type string1 -%type string2 +%token STRING1 STRING2 +%type string1 string2 %union @{ char character; @} %token CHR %type chr @@ -5028,7 +5145,9 @@ value by default. However, when the parser displays a @code{STRING1} or a @code{string1}, it formats it as a string in double quotes. It performs only the second @code{%printer} in this case, so it prints only once. Finally, the parser print @samp{<>} for any symbol, such as @code{TAGLESS}, -that has no semantic type tag. See also +that has no semantic type tag. @xref{Mfcalc Traces, ,Enabling Debug Traces +for @code{mfcalc}}, for a complete example. + @node Expect Decl @@ -5268,7 +5387,7 @@ Here is a summary of the declarations used to define a grammar: @deffn {Directive} %union Declare the collection of data types that semantic values may have -(@pxref{Union Decl, ,The Collection of Value Types}). +(@pxref{Union Decl, ,The Union Declaration}). @end deffn @deffn {Directive} %token @@ -5336,6 +5455,7 @@ parse.trace}. @deffn {Directive} %define @var{variable} @deffnx {Directive} %define @var{variable} @var{value} +@deffnx {Directive} %define @var{variable} @{@var{value}@} @deffnx {Directive} %define @var{variable} "@var{value}" Define a variable to adjust Bison's behavior. @xref{%define Summary}. @end deffn @@ -5385,7 +5505,7 @@ preprocessor guard: @samp{YY_@var{PREFIX}_@var{FILE}_INCLUDED}, where uppercase, with each series of non alphanumerical characters converted to a single underscore. -For instance with @samp{%define api.prefix "calc"} and @samp{%defines +For instance with @samp{%define api.prefix @{calc@}} and @samp{%defines "lib/parse.h"}, the header will be guarded as follows. @example #ifndef YY_CALC_LIB_PARSE_H_INCLUDED @@ -5547,17 +5667,17 @@ features are associated with variables, which are assigned by the @deffn {Directive} %define @var{variable} @deffnx {Directive} %define @var{variable} @var{value} +@deffnx {Directive} %define @var{variable} @{@var{value}@} @deffnx {Directive} %define @var{variable} "@var{value}" Define @var{variable} to @var{value}. -@var{value} must be placed in quotation marks if it contains any -character other than a letter, underscore, period, or non-initial dash -or digit. Omitting @code{"@var{value}"} entirely is always equivalent -to specifying @code{""}. +The type of the values depend on the syntax. Braces denote value in the +target language (e.g., a namespace, a type, etc.). Keyword values (no +delimiters) denote finite choice (e.g., a variation of a feature). String +values denote remaining cases (e.g., a file name). -It is an error if a @var{variable} is defined by @code{%define} -multiple times, but see @ref{Bison Options,,-D -@var{name}[=@var{value}]}. +It is an error if a @var{variable} is defined by @code{%define} multiple +times, but see @ref{Bison Options,,-D @var{name}[=@var{value}]}. @end deffn The rest of this section summarizes variables and values that @@ -5586,6 +5706,7 @@ Summary,,%skeleton}). Unaccepted @var{variable}s produce an error. Some of the accepted @var{variable}s are described below. +@c ================================================== api.namespace @deffn Directive {%define api.namespace} @{@var{namespace}@} @itemize @item Languages(s): C++ @@ -5638,7 +5759,7 @@ The parser namespace is @code{foo} and @code{yylex} is referenced as @c api.namespace @c ================================================== api.location.type -@deffn {Directive} {%define api.location.type} @var{type} +@deffn {Directive} {%define api.location.type} @{@var{type}@} @itemize @bullet @item Language(s): C++, Java @@ -5657,7 +5778,7 @@ Introduced in Bison 2.7 for C, C++ and Java. Introduced under the name @end deffn @c ================================================== api.prefix -@deffn {Directive} {%define api.prefix} @var{prefix} +@deffn {Directive} {%define api.prefix} @{@var{prefix}@} @itemize @bullet @item Language(s): All @@ -5674,7 +5795,7 @@ Introduced in Bison 2.7 for C, C++ and Java. Introduced under the name @end deffn @c ================================================== api.pure -@deffn Directive {%define api.pure} +@deffn Directive {%define api.pure} @var{purity} @itemize @bullet @item Language(s): C @@ -5762,14 +5883,14 @@ Boolean. @item Default Value: @code{false} @item History: -introduced in Bison 2.8 +introduced in Bison 3.0 @end itemize @end deffn @c api.token.constructor @c ================================================== api.token.prefix -@deffn Directive {%define api.token.prefix} @var{prefix} +@deffn Directive {%define api.token.prefix} @{@var{prefix}@} @itemize @item Languages(s): all @@ -5780,7 +5901,7 @@ target language. For instance @example %token FILE for ERROR -%define api.token.prefix "TOK_" +%define api.token.prefix @{TOK_@} %% start: FILE for ERROR; @end example @@ -5791,8 +5912,13 @@ and @code{TOK_ERROR} in the generated source files. In particular, the scanner must use these prefixed token names, while the grammar itself may still use the short names (as in the sample rule given above). The generated informational files (@file{*.output}, @file{*.xml}, -@file{*.dot}) are not modified by this prefix. See @ref{Calc++ Parser} -and @ref{Calc++ Scanner}, for a complete example. +@file{*.dot}) are not modified by this prefix. + +Bison also prefixes the generated member names of the semantic value union. +@xref{Type Generation,, Generating the Semantic Value Type}, for more +details. + +See @ref{Calc++ Parser} and @ref{Calc++ Scanner}, for a complete example. @item Accepted Values: Any string. Should be a valid identifier prefix in the target language, @@ -5802,32 +5928,132 @@ letters, underscores, and ---not at the beginning--- digits). @item Default Value: empty @item History: -introduced in Bison 2.8 +introduced in Bison 3.0 @end itemize @end deffn @c api.token.prefix @c ================================================== api.value.type -@deffn Directive {%define api.value.type} @var{type} +@deffn Directive {%define api.value.type} @var{support} +@deffnx Directive {%define api.value.type} @{@var{type}@} @itemize @bullet @item Language(s): -C++ +all @item Purpose: -Request variant-based semantic values. +The type for semantic values. + +@item Accepted Values: +@table @asis +@item @samp{@{@}} +This grammar has no semantic value at all. This is not properly supported +yet. +@item @samp{union-directive} (C, C++) +The type is defined thanks to the @code{%union} directive. You don't have +to define @code{api.value.type} in that case, using @code{%union} suffices. +@xref{Union Decl, ,The Union Declaration}. +For instance: +@example +%define api.value.type union-directive +%union +@{ + int ival; + char *sval; +@} +%token INT "integer" +%token STR "string" +@end example + +@item @samp{union} (C, C++) +The symbols are defined with type names, from which Bison will generate a +@code{union}. For instance: +@example +%define api.value.type union +%token INT "integer" +%token STR "string" +@end example +This feature needs user feedback to stabilize. Note that most C++ objects +cannot be stored in a @code{union}. + +@item @samp{variant} (C++) +This is similar to @code{union}, but special storage techniques are used to +allow any kind of C++ object to be used. For instance: +@example +%define api.value.type variant +%token INT "integer" +%token STR "string" +@end example +This feature needs user feedback to stabilize. @xref{C++ Variants}. +@item @samp{@{@var{type}@}} +Use this @var{type} as semantic value. +@example +%code requires +@{ + struct my_value + @{ + enum + @{ + is_int, is_str + @} kind; + union + @{ + int ival; + char *sval; + @} u; + @}; +@} +%define api.value.type @{struct my_value@} +%token INT "integer" +%token STR "string" +@end example +@end table + @item Default Value: -FIXME: +@itemize @minus +@item +@code{union-directive} if @code{%union} is used, otherwise @dots{} +@item +@code{int} if type tags are used (i.e., @samp{%token <@var{type}>@dots{}} or +@samp{%type <@var{type}>@dots{}} is used), otherwise @dots{} +@item +undefined. +@end itemize + @item History: -introduced in Bison 2.8. Was introduced for Java only in 2.3b as +introduced in Bison 3.0. Was introduced for Java only in 2.3b as @code{stype}. @end itemize @end deffn @c api.value.type +@c ================================================== api.value.union.name +@deffn Directive {%define api.value.union.name} @var{name} +@itemize @bullet +@item Language(s): +C + +@item Purpose: +The tag of the generated @code{union} (@emph{not} the name of the +@code{typedef}). This variable is set to @code{@var{id}} when @samp{%union +@var{id}} is used. There is no clear reason to give this union a name. + +@item Accepted Values: +Any valid identifier. + +@item Default Value: +@code{YYSTYPE}. + +@item History: +Introduced in Bison 3.0.3. +@end itemize +@end deffn +@c api.value.type + + @c ================================================== location_type @deffn Directive {%define location_type} Obsoleted by @code{api.location.type} since Bison 2.7. @@ -5853,8 +6079,8 @@ feedback will help to stabilize it.) @item @code{most} otherwise. @end itemize @item History: -introduced as @code{lr.default-reduction} in 2.5, renamed as -@code{lr.default-reduction} in 2.8. +introduced as @code{lr.default-reductions} in 2.5, renamed as +@code{lr.default-reduction} in 3.0. @end itemize @end deffn @@ -5871,7 +6097,7 @@ remain in the parser tables. @xref{Unreachable States}. @item History: introduced as @code{lr.keep_unreachable_states} in 2.3b, renamed as @code{lr.keep-unreachable-states} in 2.5, and as -@code{lr.keep-unreachable-state} in 2.8. +@code{lr.keep-unreachable-state} in 3.0. @end itemize @end deffn @c lr.keep-unreachable-state @@ -5919,7 +6145,7 @@ destroyed properly. This option checks these constraints. @c ================================================== parse.error -@deffn Directive {%define parse.error} +@deffn Directive {%define parse.error} @var{verbosity} @itemize @item Languages(s): all @@ -5946,7 +6172,7 @@ However, this report can often be incorrect when LAC is not enabled @c ================================================== parse.lac -@deffn Directive {%define parse.lac} +@deffn Directive {%define parse.lac} @var{when} @itemize @item Languages(s): C (deterministic parsers only) @@ -5969,7 +6195,7 @@ syntax error handling. @xref{LAC}. @xref{Tracing, ,Tracing Your Parser}. In C/C++, define the macro @code{YYDEBUG} (or @code{@var{prefix}DEBUG} with -@samp{%define api.prefix @var{prefix}}), see @ref{Multiple Parsers, +@samp{%define api.prefix @{@var{prefix}@}}), see @ref{Multiple Parsers, ,Multiple Parsers in the Same Program}) to 1 in the parser implementation file if it is not already defined, so that the debugging facilities are compiled. @@ -6032,10 +6258,11 @@ qualifiers produce an error. Some of the accepted qualifiers are: @item Language(s): C, C++ @item Purpose: This is the best place to write dependency code required for -@code{YYSTYPE} and @code{YYLTYPE}. -In other words, it's the best place to define types referenced in @code{%union} -directives, and it's the best place to override Bison's default @code{YYSTYPE} -and @code{YYLTYPE} definitions. +@code{YYSTYPE} and @code{YYLTYPE}. In other words, it's the best place to +define types referenced in @code{%union} directives. If you use +@code{#define} to override Bison's default @code{YYSTYPE} and @code{YYLTYPE} +definitions, then it is also the best place. However you should rather +@code{%define} @code{api.value.type} and @code{api.location.type}. @item Location(s): The parser header file and the parser implementation file before the Bison-generated @code{YYSTYPE} and @code{YYLTYPE} @@ -6111,7 +6338,7 @@ The easy way to do this is to define the @code{%define} variable @code{api.prefix}. With different @code{api.prefix}s it is guaranteed that headers do not conflict when included together, and that compiled objects can be linked together too. Specifying @samp{%define api.prefix -@var{prefix}} (or passing the option @samp{-Dapi.prefix=@var{prefix}}, see +@{@var{prefix}@}} (or passing the option @samp{-Dapi.prefix=@{@var{prefix}@}}, see @ref{Invocation, ,Invoking Bison}) renames the interface functions and variables of the Bison parser to start with @var{prefix} instead of @samp{yy}, and all the macros to start by @var{PREFIX} (i.e., @var{prefix} @@ -6125,7 +6352,7 @@ The renamed symbols include @code{yyparse}, @code{yylex}, @code{yyerror}, @code{YYSTYPE}, @code{YYLTYPE}, and @code{YYDEBUG}, which is treated specifically --- more about this below. -For example, if you use @samp{%define api.prefix c}, the names become +For example, if you use @samp{%define api.prefix @{c@}}, the names become @code{cparse}, @code{clex}, @dots{}, @code{CSTYPE}, @code{CLTYPE}, and so on. @@ -6507,7 +6734,7 @@ Thus, if the type is @code{int} (the default), you might write this in When you are using multiple data types, @code{yylval}'s type is a union made from the @code{%union} declaration (@pxref{Union Decl, ,The -Collection of Value Types}). So when you store a token's value, you +Union Declaration}). So when you store a token's value, you must use the proper member of the union. If the @code{%union} declaration looks like this: @@ -9358,7 +9585,7 @@ enabled if and only if @code{YYDEBUG} is nonzero. @item the option @option{-t} (POSIX Yacc compliant) @itemx the option @option{--debug} (Bison extension) Use the @samp{-t} option when you run Bison (@pxref{Invocation, ,Invoking -Bison}). With @samp{%define api.prefix c}, it defines @code{CDEBUG} to 1, +Bison}). With @samp{%define api.prefix @{c@}}, it defines @code{CDEBUG} to 1, otherwise it defines @code{YYDEBUG} to 1. @item the directive @samp{%debug} @@ -9450,7 +9677,7 @@ prologue: /* Formatting semantic values. */ %printer @{ fprintf (yyoutput, "%s", $$->name); @} VAR; %printer @{ fprintf (yyoutput, "%s()", $$->name); @} FNCT; -%printer @{ fprintf (yyoutput, "%g", $$); @} ; +%printer @{ fprintf (yyoutput, "%g", $$); @} ; @end example The @code{%define} directive instructs Bison to generate run-time trace @@ -9463,8 +9690,8 @@ ill-named) @code{%verbose} directive. The set of @code{%printer} directives demonstrates how to format the semantic value in the traces. Note that the specification can be done either on the symbol type (e.g., @code{VAR} or @code{FNCT}), or on the type -tag: since @code{} is the type for both @code{NUM} and @code{exp}, this -printer will be used for them. +tag: since @code{} is the type for both @code{NUM} and @code{exp}, +this printer will be used for them. Here is a sample of the information provided by run-time traces. The traces are sent onto standard error. @@ -9514,7 +9741,7 @@ Entering state 24 @noindent The previous reduction demonstrates the @code{%printer} directive for -@code{}: both the token @code{NUM} and the resulting nonterminal +@code{}: both the token @code{NUM} and the resulting nonterminal @code{exp} have @samp{1} as value. @example @@ -9866,18 +10093,16 @@ A category can be turned off by prefixing its name with @samp{no-}. For instance, @option{-Wno-yacc} will hide the warnings about POSIX Yacc incompatibilities. -@item -Werror[=@var{category}] -@itemx -Wno-error[=@var{category}] -Enable warnings falling in @var{category}, and treat them as errors. If no -@var{category} is given, it defaults to making all enabled warnings into errors. +@item -Werror +Turn enabled warnings for every @var{category} into errors, unless they are +explicitly disabled by @option{-Wno-error=@var{category}}. + +@item -Werror=@var{category} +Enable warnings falling in @var{category}, and treat them as errors. @var{category} is the same as for @option{--warnings}, with the exception that it may not be prefixed with @samp{no-} (see above). -Prefixed with @samp{no}, it deactivates the error treatment for this -@var{category}. However, the warning itself won't be disabled, or enabled, by -this option. - Note that the precedence of the @samp{=} and @samp{,} operators is such that the following commands are @emph{not} equivalent, as the first will not treat S/R conflicts as errors. @@ -9887,6 +10112,14 @@ $ bison -Werror=yacc,conflicts-sr input.y $ bison -Werror=yacc,error=conflicts-sr input.y @end example +@item -Wno-error +Do not turn enabled warnings for every @var{category} into errors, unless +they are explicitly enabled by @option{-Werror=@var{category}}. + +@item -Wno-error=@var{category} +Deactivate the error treatment for this @var{category}. However, the warning +itself won't be disabled, or enabled, by this option. + @item -f [@var{feature}] @itemx --feature[=@var{feature}] Activate miscellaneous @var{feature}. @var{feature} can be one of: @@ -10243,7 +10476,7 @@ approach is provided, based on variants (@pxref{C++ Variants}). @subsubsection C++ Unions The @code{%union} directive works as for C, see @ref{Union Decl, ,The -Collection of Value Types}. In particular it produces a genuine +Union Declaration}. In particular it produces a genuine @code{union}, which have a few specific features in C++. @itemize @minus @item @@ -10395,16 +10628,18 @@ filename_type "@var{type}"}. The line, starting at 1. @end deftypeivar -@deftypemethod {position} {uint} lines (int @var{height} = 1) -Advance by @var{height} lines, resetting the column number. +@deftypemethod {position} {void} lines (int @var{height} = 1) +If @var{height} is not null, advance by @var{height} lines, resetting the +column number. The resulting line number cannot be less than 1. @end deftypemethod @deftypeivar {position} {uint} column The column, starting at 1. @end deftypeivar -@deftypemethod {position} {uint} columns (int @var{width} = 1) -Advance by @var{width} columns, without changing the line number. +@deftypemethod {position} {void} columns (int @var{width} = 1) +Advance by @var{width} columns, without changing the line number. The +resulting column number cannot be less than 1. @end deftypemethod @deftypemethod {position} {position&} operator+= (int @var{width}) @@ -10446,15 +10681,22 @@ Reset the location to an empty range at the given values. The first, inclusive, position of the range, and the first beyond. @end deftypeivar -@deftypemethod {location} {uint} columns (int @var{width} = 1) -@deftypemethodx {location} {uint} lines (int @var{height} = 1) -Advance the @code{end} position. +@deftypemethod {location} {void} columns (int @var{width} = 1) +@deftypemethodx {location} {void} lines (int @var{height} = 1) +Forwarded to the @code{end} position. @end deftypemethod -@deftypemethod {location} {location} operator+ (const location& @var{end}) -@deftypemethodx {location} {location} operator+ (int @var{width}) +@deftypemethod {location} {location} operator+ (int @var{width}) @deftypemethodx {location} {location} operator+= (int @var{width}) -Various forms of syntactic sugar. +@deftypemethodx {location} {location} operator- (int @var{width}) +@deftypemethodx {location} {location} operator-= (int @var{width}) +Various forms of syntactic sugar for @code{columns}. +@end deftypemethod + +@deftypemethod {location} {location} operator+ (const location& @var{end}) +@deftypemethodx {location} {location} operator+= (const location& @var{end}) +Join two locations: starts at the position of the first one, and ends at the +position of the second. @end deftypemethod @deftypemethod {location} {void} step () @@ -10480,7 +10722,7 @@ Instead of using the built-in types you may use the @code{%define} variable @code{api.location.type} to specify your own type: @example -%define api.location.type @var{LocationType} +%define api.location.type @{@var{LocationType}@} @end example The requirements over your @var{LocationType} are: @@ -10517,7 +10759,7 @@ parser @file{master/parser.yy} might use: @example %defines %locations -%define namespace "master::" +%define api.namespace @{master::@} @end example @noindent @@ -10525,7 +10767,7 @@ to generate the @file{master/position.hh} and @file{master/location.hh} files, reused by other parsers as follows: @example -%define api.location.type "master::location" +%define api.location.type @{master::location@} %code requires @{ #include @} @end example @@ -10540,7 +10782,7 @@ files, reused by other parsers as follows: The output files @file{@var{output}.hh} and @file{@var{output}.cc} declare and define the parser class in the namespace @code{yy}. The class name defaults to @code{parser}, but may be changed using -@samp{%define parser_class_name "@var{name}"}. The interface of +@samp{%define parser_class_name @{@var{name}@}}. The interface of this class is detailed below. It can be extended using the @code{%parse-param} feature: its semantics is slightly changed since it describes an additional member of the parser class, and an @@ -10717,7 +10959,7 @@ also pass the @var{location}. For instance, given the following declarations: @example -%define api.token.prefix "TOK_" +%define api.token.prefix @{TOK_@} %token IDENTIFIER; %token INTEGER; %token COLON; @@ -10945,7 +11187,7 @@ the grammar for. %skeleton "lalr1.cc" /* -*- C++ -*- */ %require "@value{VERSION}" %defines -%define parser_class_name "calcxx_parser" +%define parser_class_name @{calcxx_parser@} @end example @noindent @@ -11043,7 +11285,7 @@ tokens with @code{TOK_} (@pxref{%define Summary,,api.token.prefix}). @comment file: calc++-parser.yy @example -%define api.token.prefix "TOK_" +%define api.token.prefix @{TOK_@} %token END 0 "end of file" ASSIGN ":=" @@ -11298,6 +11540,7 @@ main (int argc, char *argv[]) * Java Parser Interface:: Instantiating and running the parser * Java Scanner Interface:: Specifying the scanner for the parser * Java Action Features:: Special features for use in actions +* Java Push Parser Interface:: Instantiating and running the a push parser * Java Differences:: Differences between C/C++ and Java Grammars * Java Declarations Summary:: List of Bison declarations used with Java @end menu @@ -11379,7 +11622,7 @@ superclass of all the semantic values using the @samp{%define api.value.type} directive. For example, after the following declaration: @example -%define api.value.type "ASTNode" +%define api.value.type @{ASTNode@} @end example @noindent @@ -11414,11 +11657,11 @@ class defines a @dfn{position}, a single point in a file; Bison itself defines a class representing a @dfn{location}, a range composed of a pair of positions (possibly spanning several files). The location class is an inner class of the parser; the name is @code{Location} by default, and may also be -renamed using @code{%define api.location.type "@var{class-name}"}. +renamed using @code{%define api.location.type @{@var{class-name}@}}. The location class treats the position as a completely opaque value. By default, the class name is @code{Position}, but this can be changed -with @code{%define api.position.type "@var{class-name}"}. This class must +with @code{%define api.position.type @{@var{class-name}@}}. This class must be supplied by the user. @@ -11453,7 +11696,7 @@ properly, the position class should override the @code{equals} and The name of the generated parser class defaults to @code{YYParser}. The @code{YY} prefix may be changed using the @code{%name-prefix} directive or the @option{-p}/@option{--name-prefix} option. Alternatively, use -@samp{%define parser_class_name "@var{name}"} to give a custom name to +@samp{%define parser_class_name @{@var{name}@}} to give a custom name to the class. The interface of this class is detailed below. By default, the parser class has package visibility. A declaration @@ -11462,7 +11705,7 @@ according to the Java language specification, the name of the @file{.java} file should match the name of the class in this case. Similarly, you can use @code{abstract}, @code{final} and @code{strictfp} with the @code{%define} declaration to add other modifiers to the parser class. -A single @samp{%define annotations "@var{annotations}"} directive can +A single @samp{%define annotations @{@var{annotations}@}} directive can be used to add any number of annotations to the parser class. The Java package name of the parser class can be specified using the @@ -11580,7 +11823,7 @@ In both cases, the scanner has to implement the following methods. @deftypemethod {Lexer} {void} yyerror (Location @var{loc}, String @var{msg}) This method is defined by the user to emit an error message. The first parameter is omitted if location tracking is not active. Its type can be -changed using @code{%define api.location.type "@var{class-name}".} +changed using @code{%define api.location.type @{@var{class-name}@}}. @end deftypemethod @deftypemethod {Lexer} {int} yylex () @@ -11599,17 +11842,16 @@ Return respectively the first position of the last token that methods are not needed unless location tracking is active. The return type can be changed using @code{%define api.position.type -"@var{class-name}".} +@{@var{class-name}@}}. @end deftypemethod @deftypemethod {Lexer} {Object} getLVal () Return the semantic value of the last token that yylex returned. The return type can be changed using @samp{%define api.value.type -"@var{class-name}".} +@{@var{class-name}@}}. @end deftypemethod - @node Java Action Features @subsection Special Features for Use in Java Actions @@ -11688,6 +11930,73 @@ instance in use. The @code{Location} and @code{Position} parameters are available only if location tracking is active. @end deftypefn +@node Java Push Parser Interface +@subsection Java Push Parser Interface +@c - define push_parse +@findex %define api.push-pull + +(The current push parsing interface is experimental and may evolve. More +user feedback will help to stabilize it.) + +Normally, Bison generates a pull parser for Java. +The following Bison declaration says that you want the parser to be a push +parser (@pxref{%define Summary,,api.push-pull}): + +@example +%define api.push-pull push +@end example + +Most of the discussion about the Java pull Parser Interface, (@pxref{Java +Parser Interface}) applies to the push parser interface as well. + +When generating a push parser, the method @code{push_parse} is created with +the following signature (depending on if locations are enabled). + +@deftypemethod {YYParser} {void} push_parse ({int} @var{token}, {Object} @var{yylval}) +@deftypemethodx {YYParser} {void} push_parse ({int} @var{token}, {Object} @var{yylval}, {Location} @var{yyloc}) +@deftypemethodx {YYParser} {void} push_parse ({int} @var{token}, {Object} @var{yylval}, {Position} @var{yypos}) +@end deftypemethod + +The primary difference with respect to a pull parser is that the parser +method @code{push_parse} is invoked repeatedly to parse each token. This +function is available if either the "%define api.push-pull push" or "%define +api.push-pull both" declaration is used (@pxref{%define +Summary,,api.push-pull}). The @code{Location} and @code{Position} +parameters are available only if location tracking is active. + +The value returned by the @code{push_parse} method is one of the following +four constants: @code{YYABORT}, @code{YYACCEPT}, @code{YYERROR}, or +@code{YYPUSH_MORE}. This new value, @code{YYPUSH_MORE}, may be returned if +more input is required to finish parsing the grammar. + +If api.push-pull is declared as @code{both}, then the generated parser class +will also implement the @code{parse} method. This method's body is a loop +that repeatedly invokes the scanner and then passes the values obtained from +the scanner to the @code{push_parse} method. + +There is one additional complication. Technically, the push parser does not +need to know about the scanner (i.e. an object implementing the +@code{YYParser.Lexer} interface), but it does need access to the +@code{yyerror} method. Currently, the @code{yyerror} method is defined in +the @code{YYParser.Lexer} interface. Hence, an implementation of that +interface is still required in order to provide an implementation of +@code{yyerror}. The current approach (and subject to change) is to require +the @code{YYParser} constructor to be given an object implementing the +@code{YYParser.Lexer} interface. This object need only implement the +@code{yyerror} method; the other methods can be stubbed since they will +never be invoked. The simplest way to do this is to add a trivial scanner +implementation to your grammar file using whatever implementation of +@code{yyerror} is desired. The following code sample shows a simple way to +accomplish this. + +@example +%code lexer +@{ + public Object getLVal () @{return null;@} + public int yylex () @{return 0;@} + public void yyerror (String s) @{System.err.println(s);@} +@} +@end example @node Java Differences @subsection Differences between C/C++ and Java Grammars @@ -11827,12 +12136,12 @@ Whether the parser class is declared @code{abstract}. Default is false. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define annotations} "@var{annotations}" +@deffn {Directive} {%define annotations} @{@var{annotations}@} The Java annotations for the parser class. Default is none. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define extends} "@var{superclass}" +@deffn {Directive} {%define extends} @{@var{superclass}@} The superclass of the parser class. Default is none. @xref{Java Bison Interface}. @end deffn @@ -11842,25 +12151,25 @@ Whether the parser class is declared @code{final}. Default is false. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define implements} "@var{interfaces}" +@deffn {Directive} {%define implements} @{@var{interfaces}@} The implemented interfaces of the parser class, a comma-separated list. Default is none. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define init_throws} "@var{exceptions}" +@deffn {Directive} {%define init_throws} @{@var{exceptions}@} The exceptions thrown by @code{%code init} from the parser class constructor. Default is none. @xref{Java Parser Interface}. @end deffn -@deffn {Directive} {%define lex_throws} "@var{exceptions}" +@deffn {Directive} {%define lex_throws} @{@var{exceptions}@} The exceptions thrown by the @code{yylex} method of the lexer, a comma-separated list. Default is @code{java.io.IOException}. @xref{Java Scanner Interface}. @end deffn -@deffn {Directive} {%define api.location.type} "@var{class}" +@deffn {Directive} {%define api.location.type} @{@var{class}@} The name of the class used for locations (a range between two positions). This class is generated as an inner class of the parser class by @command{bison}. Default is @code{Location}. @@ -11868,18 +12177,18 @@ Formerly named @code{location_type}. @xref{Java Location Values}. @end deffn -@deffn {Directive} {%define package} "@var{package}" +@deffn {Directive} {%define package} @{@var{package}@} The package to put the parser class in. Default is none. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define parser_class_name} "@var{name}" +@deffn {Directive} {%define parser_class_name} @{@var{name}@} The name of the parser class. Default is @code{YYParser} or @code{@var{name-prefix}Parser}. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define api.position.type} "@var{class}" +@deffn {Directive} {%define api.position.type} @{@var{class}@} The name of the class used for positions. This class must be supplied by the user. Default is @code{Position}. Formerly named @code{position_type}. @@ -11891,7 +12200,7 @@ Whether the parser class is declared @code{public}. Default is false. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define api.value.type} "@var{class}" +@deffn {Directive} {%define api.value.type} @{@var{class}@} The base type of semantic values. Default is @code{Object}. @xref{Java Semantic Values}. @end deffn @@ -11901,7 +12210,7 @@ Whether the parser class is declared @code{strictfp}. Default is false. @xref{Java Bison Interface}. @end deffn -@deffn {Directive} {%define throws} "@var{exceptions}" +@deffn {Directive} {%define throws} @{@var{exceptions}@} The exceptions thrown by user-supplied parser actions and @code{%initial-action}, a comma-separated list. Default is none. @xref{Java Parser Interface}. @@ -12455,6 +12764,7 @@ Precedence}. @deffn {Directive} %define @var{variable} @deffnx {Directive} %define @var{variable} @var{value} +@deffnx {Directive} %define @var{variable} @{@var{value}@} @deffnx {Directive} %define @var{variable} "@var{value}" Define a variable to adjust Bison's behavior. @xref{%define Summary}. @end deffn @@ -12558,7 +12868,7 @@ push parser, @code{yypush_parse}, @code{yypull_parse}, @code{yypstate}, @code{yypstate_new} and @code{yypstate_delete} will also be renamed. For example, if you use @samp{%name-prefix "c_"}, the names become @code{c_parse}, @code{c_lex}, and so on. For C++ parsers, see the -@code{%define namespace} documentation in this section. +@code{%define api.namespace} documentation in this section. @end deffn @@ -12655,7 +12965,7 @@ The predefined token onto which all undefined values returned by @deffn {Directive} %union Bison declaration to specify several possible data types for semantic -values. @xref{Union Decl, ,The Collection of Value Types}. +values. @xref{Union Decl, ,The Union Declaration}. @end deffn @deffn {Macro} YYABORT @@ -12860,6 +13170,7 @@ require some expertise in low-level implementation details. @end deffn @deffn {Type} YYSTYPE +Deprecated in favor of the @code{%define} variable @code{api.value.type}. Data type of semantic values; @code{int} by default. @xref{Value Type, ,Data Types of Semantic Values}. @end deffn