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Formatting changes.

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Akim Demaille
2001-11-05 09:14:55 +00:00
parent 951366c145
commit 1964ad8c34
1 changed files with 13 additions and 10 deletions
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doc/bison.texinfo
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@@ -855,11 +855,12 @@ The declarations section (@pxref{Prologue, , The prologue}) contains two
preprocessor directives. preprocessor directives.
The @code{#define} directive defines the macro @code{YYSTYPE}, thus The @code{#define} directive defines the macro @code{YYSTYPE}, thus
specifying the C data type for semantic values of both tokens and groupings specifying the C data type for semantic values of both tokens and
(@pxref{Value Type, ,Data Types of Semantic Values}). The Bison parser will use whatever type groupings (@pxref{Value Type, ,Data Types of Semantic Values}). The
@code{YYSTYPE} is defined as; if you don't define it, @code{int} is the Bison parser will use whatever type @code{YYSTYPE} is defined as; if you
default. Because we specify @code{double}, each token and each expression don't define it, @code{int} is the default. Because we specify
has an associated value, which is a floating point number. @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 The @code{#include} directive is used to declare the exponentiation
function @code{pow}. function @code{pow}.
@@ -1066,10 +1067,11 @@ token type is an identifier, that identifier is defined by Bison as a C
macro whose definition is the appropriate number. In this example, macro whose definition is the appropriate number. In this example,
therefore, @code{NUM} becomes a macro for @code{yylex} to use. 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 The semantic value of the token (if it has one) is stored into the
variable @code{yylval}, which is where the Bison parser will look for it. global variable @code{yylval}, which is where the Bison parser will look
(The C data type of @code{yylval} is @code{YYSTYPE}, which was defined for it. (The C data type of @code{yylval} is @code{YYSTYPE}, which was
at the beginning of the grammar; @pxref{Rpcalc Decls, ,Declarations for @code{rpcalc}}.) defined at the beginning of the grammar; @pxref{Rpcalc Decls,
,Declarations for @code{rpcalc}}.)
A token type code of zero is returned if the end-of-file is encountered. A token type code of zero is returned if the end-of-file is encountered.
(Bison recognizes any nonpositive value as indicating the end of the (Bison recognizes any nonpositive value as indicating the end of the
@@ -2375,7 +2377,8 @@ the numbers associated with @var{x} and @var{y}.
In a simple program it may be sufficient to use the same data type for In a simple program it may be sufficient to use the same data type for
the semantic values of all language constructs. This was true in the the semantic values of all language constructs. This was true in the
RPN and infix calculator examples (@pxref{RPN Calc, ,Reverse Polish Notation Calculator}). RPN and infix calculator examples (@pxref{RPN Calc, ,Reverse Polish
Notation Calculator}).
Bison's default is to use type @code{int} for all semantic values. To Bison's default is to use type @code{int} for all semantic values. To
specify some other type, define @code{YYSTYPE} as a macro, like this: specify some other type, define @code{YYSTYPE} as a macro, like this: