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* src/reader.c (parse_union_decl): Output yystype/YYSTYPE as we do
with yyltype/YYLTYPE. This allows inclusion of the generated header within the parser if the compiler, such as GGC, accepts multiple equivalent #defines.
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@@ -34,7 +34,7 @@ File: bison.info, Node: Top, Next: Introduction, Up: (dir)
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Bison
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*****
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This manual documents version 1.30a of Bison, updated 4 November
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This manual documents version 1.30a of Bison, updated 5 November
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2001.
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* Menu:
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@@ -855,11 +855,12 @@ The C declarations section (@pxref{C Declarations, ,The C Declarations Section})
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preprocessor directives.
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The @code{#define} directive defines the macro @code{YYSTYPE}, thus
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specifying the C data type for semantic values of both tokens and groupings
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(@pxref{Value Type, ,Data Types of Semantic Values}). The Bison parser will use whatever type
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@code{YYSTYPE} is defined as; if you don't define it, @code{int} is the
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default. Because we specify @code{double}, each token and each expression
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has an associated value, which is a floating point number.
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specifying the C data type for semantic values of both tokens and
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groupings (@pxref{Value Type, ,Data Types of Semantic Values}). The
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Bison parser will use whatever type @code{YYSTYPE} is defined as; if you
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don't define it, @code{int} is the default. Because we specify
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@code{double}, each token and each expression has an associated value,
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which is a floating point number.
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The @code{#include} directive is used to declare the exponentiation
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function @code{pow}.
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@@ -1066,10 +1067,11 @@ token type is an identifier, that identifier is defined by Bison as a C
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macro whose definition is the appropriate number. In this example,
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therefore, @code{NUM} becomes a macro for @code{yylex} to use.
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The semantic value of the token (if it has one) is stored into the global
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variable @code{yylval}, which is where the Bison parser will look for it.
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(The C data type of @code{yylval} is @code{YYSTYPE}, which was defined
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at the beginning of the grammar; @pxref{Rpcalc Decls, ,Declarations for @code{rpcalc}}.)
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The semantic value of the token (if it has one) is stored into the
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global variable @code{yylval}, which is where the Bison parser will look
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for it. (The C data type of @code{yylval} is @code{YYSTYPE}, which was
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defined at the beginning of the grammar; @pxref{Rpcalc Decls,
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,Declarations for @code{rpcalc}}.)
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A token type code of zero is returned if the end-of-file is encountered.
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(Bison recognizes any nonpositive value as indicating the end of the
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@@ -2374,7 +2376,8 @@ the numbers associated with @var{x} and @var{y}.
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In a simple program it may be sufficient to use the same data type for
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the semantic values of all language constructs. This was true in the
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RPN and infix calculator examples (@pxref{RPN Calc, ,Reverse Polish Notation Calculator}).
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RPN and infix calculator examples (@pxref{RPN Calc, ,Reverse Polish
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Notation Calculator}).
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Bison's default is to use type @code{int} for all semantic values. To
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specify some other type, define @code{YYSTYPE} as a macro, like this:
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@@ -1,4 +1,4 @@
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@set UPDATED 4 November 2001
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@set UPDATED 5 November 2001
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@set UPDATED-MONTH November 2001
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@set EDITION 1.30a
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@set VERSION 1.30a
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@@ -1,4 +1,4 @@
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@set UPDATED 4 November 2001
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@set UPDATED 5 November 2001
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@set UPDATED-MONTH November 2001
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@set EDITION 1.30a
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@set VERSION 1.30a
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