+@end deffn
+@c api.push-pull
+
+
+
+@c ================================================== api.token.constructor
+@deffn Directive {%define api.token.constructor}
+
+@itemize @bullet
+@item Language(s):
+C++
+
+@item Purpose:
+When variant-based semantic values are enabled (@pxref{C++ Variants}),
+request that symbols be handled as a whole (type, value, and possibly
+location) in the scanner. @xref{Complete Symbols}, for details.
+
+@item Accepted Values:
+Boolean.
+
+@item Default Value:
+@code{false}
+@item History:
+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}@}
+
+@itemize
+@item Languages(s): all
+
+@item Purpose:
+Add a prefix to the token names when generating their definition in the
+target language. For instance
+
+@example
+%token FILE for ERROR
+%define api.token.prefix @{TOK_@}
+%%
+start: FILE for ERROR;
+@end example
+
+@noindent
+generates the definition of the symbols @code{TOK_FILE}, @code{TOK_for},
+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.
+
+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,
+in other words, it should typically be an identifier itself (sequence of
+letters, underscores, and ---not at the beginning--- digits).
+
+@item Default Value:
+empty
+@item History:
+introduced in Bison 3.0
+@end itemize
+@end deffn
+@c api.token.prefix
+
+
+@c ================================================== api.value.type
+@deffn Directive {%define api.value.type} @var{support}
+@deffnx Directive {%define api.value.type} @{@var{type}@}
+@itemize @bullet
+@item Language(s):
+all
+
+@item Purpose:
+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 <ival> INT "integer"
+%token <sval> 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> INT "integer"
+%token <char *> 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> INT "integer"
+%token <std::string> 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 <u.ival> INT "integer"
+%token <u.sval> STR "string"
+@end example
+@end table
+
+@item Default Value:
+@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 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
+
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