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* doc/bison.texinfo: Adjust terminologies about prologue and epilogue

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sections of Bison.
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Marc Autret
2001-09-20 18:24:27 +00:00
parent f508cb0ac9
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@@ -1,3 +1,8 @@
2001-09-20 Marc Autret <autret_m@epita.fr>
* doc/bison.texinfo: Adjust terminologies about prologue and epilogue
sections of Bison.
2001-09-19 Pascal Bart <pascal.bart@epita.fr> 2001-09-19 Pascal Bart <pascal.bart@epita.fr>
* src/bison.simple: s/%%filename/%%skeleton. * src/bison.simple: s/%%filename/%%skeleton.

109
doc/bison.texinfo
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@@ -188,7 +188,7 @@ Examples
Reverse Polish Notation Calculator Reverse Polish Notation Calculator
* Decls: Rpcalc Decls. Bison and C declarations for rpcalc. * Decls: Rpcalc Decls. Prologue (declarations) for rpcalc.
* Rules: Rpcalc Rules. Grammar Rules for rpcalc, with explanation. * Rules: Rpcalc Rules. Grammar Rules for rpcalc, with explanation.
* Lexer: Rpcalc Lexer. The lexical analyzer. * Lexer: Rpcalc Lexer. The lexical analyzer.
* Main: Rpcalc Main. The controlling function. * Main: Rpcalc Main. The controlling function.
@@ -220,10 +220,10 @@ Bison Grammar Files
Outline of a Bison Grammar Outline of a Bison Grammar
* C Declarations:: Syntax and usage of the C declarations section. * Prologue:: Syntax and usage of the prologue (declarations section).
* Bison Declarations:: Syntax and usage of the Bison declarations section. * Bison Declarations:: Syntax and usage of the Bison declarations section.
* Grammar Rules:: Syntax and usage of the grammar rules section. * Grammar Rules:: Syntax and usage of the grammar rules section.
* C Code:: Syntax and usage of the additional C code section. * Epilogue:: Syntax and usage of the epilogue (additional code section).
Defining Language Semantics Defining Language Semantics
@@ -736,7 +736,7 @@ general form of a Bison grammar file is as follows:
@example @example
%@{ %@{
@var{C declarations} @var{Prologue (declarations)}
%@} %@}
@var{Bison declarations} @var{Bison declarations}
@@ -744,15 +744,15 @@ general form of a Bison grammar file is as follows:
%% %%
@var{Grammar rules} @var{Grammar rules}
%% %%
@var{Additional C code} @var{Epilogue (additional code)}
@end example @end example
@noindent @noindent
The @samp{%%}, @samp{%@{} and @samp{%@}} are punctuation that appears The @samp{%%}, @samp{%@{} and @samp{%@}} are punctuation that appears
in every Bison grammar file to separate the sections. in every Bison grammar file to separate the sections.
The C declarations may define types and variables used in the actions. The prologue may define types and variables used in the actions. You can
You can also use preprocessor commands to define macros used there, and use also use preprocessor commands to define macros used there, and use
@code{#include} to include header files that do any of these things. @code{#include} to include header files that do any of these things.
The Bison declarations declare the names of the terminal and nonterminal The Bison declarations declare the names of the terminal and nonterminal
@@ -762,10 +762,10 @@ semantic values of various symbols.
The grammar rules define how to construct each nonterminal symbol from its The grammar rules define how to construct each nonterminal symbol from its
parts. parts.
The additional C code can contain any C code you want to use. Often the The epilogue can contain any code you want to use. Often the definition of
definition of the lexical analyzer @code{yylex} goes here, plus subroutines the lexical analyzer @code{yylex} goes here, plus subroutines called by the
called by the actions in the grammar rules. In a simple program, all the actions in the grammar rules. In a simple program, all the rest of the
rest of the program can go here. program can go here.
@node Examples, Grammar File, Concepts, Top @node Examples, Grammar File, Concepts, Top
@chapter Examples @chapter Examples
@@ -812,7 +812,7 @@ The source code for this calculator is named @file{rpcalc.y}. The
@samp{.y} extension is a convention used for Bison input files. @samp{.y} extension is a convention used for Bison input files.
@menu @menu
* Decls: Rpcalc Decls. Bison and C declarations for rpcalc. * Decls: Rpcalc Decls. Prologue (declarations) for rpcalc.
* Rules: Rpcalc Rules. Grammar Rules for rpcalc, with explanation. * Rules: Rpcalc Rules. Grammar Rules for rpcalc, with explanation.
* Lexer: Rpcalc Lexer. The lexical analyzer. * Lexer: Rpcalc Lexer. The lexical analyzer.
* Main: Rpcalc Main. The controlling function. * Main: Rpcalc Main. The controlling function.
@@ -840,7 +840,7 @@ calculator. As in C, comments are placed between @samp{/*@dots{}*/}.
%% /* Grammar rules and actions follow */ %% /* Grammar rules and actions follow */
@end example @end example
The C declarations section (@pxref{C Declarations, ,The C Declarations Section}) contains two 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
@@ -1161,8 +1161,8 @@ Before running Bison to produce a parser, we need to decide how to
arrange all the source code in one or more source files. For such a arrange all the source code in one or more source files. For such a
simple example, the easiest thing is to put everything in one file. The simple example, the easiest thing is to put everything in one file. The
definitions of @code{yylex}, @code{yyerror} and @code{main} go at the definitions of @code{yylex}, @code{yyerror} and @code{main} go at the
end, in the ``additional C code'' section of the file (@pxref{Grammar end, in the epilogue of the file
Layout, ,The Overall Layout of a Bison Grammar}). (@pxref{Grammar Layout, ,The Overall Layout of a Bison Grammar}).
For a large project, you would probably have several source files, and use For a large project, you would probably have several source files, and use
@code{make} to arrange to recompile them. @code{make} to arrange to recompile them.
@@ -1779,7 +1779,7 @@ appropriate delimiters:
@example @example
%@{ %@{
@var{C declarations} @var{Prologue}
%@} %@}
@var{Bison declarations} @var{Bison declarations}
@@ -1788,24 +1788,25 @@ appropriate delimiters:
@var{Grammar rules} @var{Grammar rules}
%% %%
@var{Additional C code} @var{Epilogue}
@end example @end example
Comments enclosed in @samp{/* @dots{} */} may appear in any of the sections. Comments enclosed in @samp{/* @dots{} */} may appear in any of the sections.
@menu @menu
* C Declarations:: Syntax and usage of the C declarations section. * Prologue:: Syntax and usage of the prologue.
* Bison Declarations:: Syntax and usage of the Bison declarations section. * Bison Declarations:: Syntax and usage of the Bison declarations section.
* Grammar Rules:: Syntax and usage of the grammar rules section. * Grammar Rules:: Syntax and usage of the grammar rules section.
* C Code:: Syntax and usage of the additional C code section. * Epilogue:: Syntax and usage of the epilogue.
@end menu @end menu
@node C Declarations, Bison Declarations, , Grammar Outline @node Prologue, Bison Declarations, , Grammar Outline
@subsection The C Declarations Section @subsection The prologue
@cindex C declarations section @cindex declarations section
@cindex declarations, C @cindex Prologue
@cindex declarations
The @var{C declarations} section contains macro definitions and The @var{prologue} section contains macro definitions and
declarations of functions and variables that are used in the actions in the declarations of functions and variables that are used in the actions in the
grammar rules. These are copied to the beginning of the parser file so grammar rules. These are copied to the beginning of the parser file so
that they precede the definition of @code{yyparse}. You can use that they precede the definition of @code{yyparse}. You can use
@@ -1813,7 +1814,7 @@ that they precede the definition of @code{yyparse}. You can use
need any C declarations, you may omit the @samp{%@{} and @samp{%@}} need any C declarations, you may omit the @samp{%@{} and @samp{%@}}
delimiters that bracket this section. delimiters that bracket this section.
@node Bison Declarations, Grammar Rules, C Declarations, Grammar Outline @node Bison Declarations, Grammar Rules, Prologue, Grammar Outline
@subsection The Bison Declarations Section @subsection The Bison Declarations Section
@cindex Bison declarations (introduction) @cindex Bison declarations (introduction)
@cindex declarations, Bison (introduction) @cindex declarations, Bison (introduction)
@@ -1823,7 +1824,7 @@ terminal and nonterminal symbols, specify precedence, and so on.
In some simple grammars you may not need any declarations. In some simple grammars you may not need any declarations.
@xref{Declarations, ,Bison Declarations}. @xref{Declarations, ,Bison Declarations}.
@node Grammar Rules, C Code, Bison Declarations, Grammar Outline @node Grammar Rules, Epilogue, Bison Declarations, Grammar Outline
@subsection The Grammar Rules Section @subsection The Grammar Rules Section
@cindex grammar rules section @cindex grammar rules section
@cindex rules section for grammar @cindex rules section for grammar
@@ -1835,18 +1836,18 @@ There must always be at least one grammar rule, and the first
@samp{%%} (which precedes the grammar rules) may never be omitted even @samp{%%} (which precedes the grammar rules) may never be omitted even
if it is the first thing in the file. if it is the first thing in the file.
@node C Code, , Grammar Rules, Grammar Outline @node Epilogue, , Grammar Rules, Grammar Outline
@subsection The Additional C Code Section @subsection The epilogue
@cindex additional C code section @cindex additional C code section
@cindex epilogue
@cindex C code, section for additional @cindex C code, section for additional
The @var{additional C code} section is copied verbatim to the end of the The @var{epilogue} is copied verbatim to the end of the parser file, just as
parser file, just as the @var{C declarations} section is copied to the the @var{prologue} is copied to the beginning. This is the most convenient
beginning. This is the most convenient place to put anything that you place to put anything that you want to have in the parser file but which need
want to have in the parser file but which need not come before the not come before the definition of @code{yyparse}. For example, the
definition of @code{yyparse}. For example, the definitions of definitions of @code{yylex} and @code{yyerror} often go here.
@code{yylex} and @code{yyerror} often go here. @xref{Interface, ,Parser @xref{Interface, ,Parser C-Language Interface}.
C-Language Interface}.
If the last section is empty, you may omit the @samp{%%} that separates it If the last section is empty, you may omit the @samp{%%} that separates it
from the grammar rules. from the grammar rules.
@@ -1854,7 +1855,7 @@ from the grammar rules.
The Bison parser itself contains many static variables whose names start The Bison parser itself contains many static variables whose names start
with @samp{yy} and many macros whose names start with @samp{YY}. It is a with @samp{yy} and many macros whose names start with @samp{YY}. It is a
good idea to avoid using any such names (except those documented in this good idea to avoid using any such names (except those documented in this
manual) in the additional C code section of the grammar file. manual) in the epilogue of the grammar file.
@node Symbols, Rules, Grammar Outline, Grammar File @node Symbols, Rules, Grammar Outline, Grammar File
@section Symbols, Terminal and Nonterminal @section Symbols, Terminal and Nonterminal
@@ -2175,8 +2176,8 @@ specify some other type, define @code{YYSTYPE} as a macro, like this:
@end example @end example
@noindent @noindent
This macro definition must go in the C declarations section of the grammar This macro definition must go in the prologue of the grammar file
file (@pxref{Grammar Outline, ,Outline of a Bison Grammar}). (@pxref{Grammar Outline, ,Outline of a Bison Grammar}).
@node Multiple Types, Actions, Value Type, Semantics @node Multiple Types, Actions, Value Type, Semantics
@subsection More Than One Value Type @subsection More Than One Value Type
@@ -3150,8 +3151,8 @@ functions that it needs to use.
Keep in mind that the parser uses many C identifiers starting with Keep in mind that the parser uses many C identifiers starting with
@samp{yy} and @samp{YY} for internal purposes. If you use such an @samp{yy} and @samp{YY} for internal purposes. If you use such an
identifier (aside from those in this manual) in an action or in additional identifier (aside from those in this manual) in an action or in epilogue
C code in the grammar file, you are likely to run into trouble. in the grammar file, you are likely to run into trouble.
@menu @menu
* Parser Function:: How to call @code{yyparse} and what it returns. * Parser Function:: How to call @code{yyparse} and what it returns.
@@ -4595,10 +4596,9 @@ Here we assume that @code{yylex} looks at the value of @code{hexflag}; when
it is nonzero, all integers are parsed in hexadecimal, and tokens starting it is nonzero, all integers are parsed in hexadecimal, and tokens starting
with letters are parsed as integers if possible. with letters are parsed as integers if possible.
The declaration of @code{hexflag} shown in the C declarations section of The declaration of @code{hexflag} shown in the prologue of the parser file
the parser file is needed to make it accessible to the actions is needed to make it accessible to the actions (@pxref{Prologue, ,The Prologue}).
(@pxref{C Declarations, ,The C Declarations Section}). You must also write the code in @code{yylex} You must also write the code in @code{yylex} to obey the flag.
to obey the flag.
@node Tie-in Recovery, , Lexical Tie-ins, Context Dependency @node Tie-in Recovery, , Lexical Tie-ins, Context Dependency
@section Lexical Tie-ins and Error Recovery @section Lexical Tie-ins and Error Recovery
@@ -4666,15 +4666,14 @@ If a Bison grammar compiles properly but doesn't do what you want when it
runs, the @code{yydebug} parser-trace feature can help you figure out why. runs, the @code{yydebug} parser-trace feature can help you figure out why.
To enable compilation of trace facilities, you must define the macro To enable compilation of trace facilities, you must define the macro
@code{YYDEBUG} when you compile the parser. You could use @code{YYDEBUG} when you compile the parser. You could use @samp{-DYYDEBUG=1}
@samp{-DYYDEBUG=1} as a compiler option or you could put @samp{#define as a compiler option or you could put @samp{#define YYDEBUG 1} in the prologue
YYDEBUG 1} in the C declarations section of the grammar file of the grammar file (@pxref{Prologue, , The Prologue}). Alternatively, use the
(@pxref{C Declarations, ,The C Declarations Section}). Alternatively, use the @samp{-t} option when @samp{-t} option when you run Bison (@pxref{Invocation, ,Invoking Bison}).
you run Bison (@pxref{Invocation, ,Invoking Bison}). We always define @code{YYDEBUG} so that We always define @code{YYDEBUG} so that debugging is always possible.
debugging is always possible.
The trace facility uses @code{stderr}, so you must add @w{@code{#include The trace facility uses @code{stderr}, so you must add
<stdio.h>}} to the C declarations section unless it is already there. @w{@code{#include <stdio.h>}} to the prologue unless it is already there.
Once you have compiled the program with trace facilities, the way to Once you have compiled the program with trace facilities, the way to
request a trace is to store a nonzero value in the variable @code{yydebug}. request a trace is to store a nonzero value in the variable @code{yydebug}.
@@ -5192,13 +5191,13 @@ These are the punctuation and delimiters used in Bison input:
@table @samp @table @samp
@item %% @item %%
Delimiter used to separate the grammar rule section from the Delimiter used to separate the grammar rule section from the
Bison declarations section or the additional C code section. Bison declarations section or the epilogue.
@xref{Grammar Layout, ,The Overall Layout of a Bison Grammar}. @xref{Grammar Layout, ,The Overall Layout of a Bison Grammar}.
@item %@{ %@} @item %@{ %@}
All code listed between @samp{%@{} and @samp{%@}} is copied directly to All code listed between @samp{%@{} and @samp{%@}} is copied directly to
the output file uninterpreted. Such code forms the ``C declarations'' the output file uninterpreted. Such code forms the prologue of the input
section of the input file. @xref{Grammar Outline, ,Outline of a Bison file. @xref{Grammar Outline, ,Outline of a Bison
Grammar}. Grammar}.
@item /*@dots{}*/ @item /*@dots{}*/