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26-fyi-doc-formatting.patch


From: Akim Demaille
Subject: 26-fyi-doc-formatting.patch
Date: Sat, 29 Dec 2001 15:15:23 +0100

Index: ChangeLog
from  Akim Demaille  <address@hidden>
        
        * doc/bison.texinfo: Formatting changes.
        
Index: TODO
--- TODO Sun, 16 Dec 2001 11:40:41 +0100 akim
+++ TODO Sat, 29 Dec 2001 08:56:13 +0100 akim
@@ -2,20 +2,37 @@
 
 * Prologue
 The %union is declared after the user C declarations. It can be
-a problem if YYSTYPE is decalred after the user part.  []
+a problem if YYSTYPE is declared after the user part.  []
 
-* --verbose
-Tell the truth about EOF.      []
+Actually, the real problem seems that the %union ought to be output
+where it was defined.  For instance, in gettext/intl/plural.y, we
+have:
+
+       %{
+       ...
+       #include "gettextP.h"
+       ...
+       %}
+
+       %union {
+         unsigned long int num;
+         enum operator op;
+         struct expression *exp;
+       }
+
+       %{
+       ...
+       static int yylex PARAMS ((YYSTYPE *lval, const char **pexp));
+       ...
+       %}
+
+Where the first part defines struct expression, the second uses it to
+define YYSTYPE, and the last uses YYSTYPE.  Only this order is valid.
 
 * --graph
 Show reductions.       []
 
-* tokendefs
-This muscle should not exist: the information it contains should be
-available from the rest of bison.  Once the information public, get
-rid of it.     []
-
-* Broken options ?.
+* Broken options ?
 ** %no-lines           [ok]
 ** %no-parser          []
 ** %pure-parser                []
@@ -33,9 +50,6 @@
             %token-table?
 *** New skeletons.     []
 
-* src/macrotab.[ch]
-Removing warnings when compiling. (gcc-warnings).      [ok]
-
 * src/print_graph.c
 Find the best graph parameters.        []
 
@@ -46,7 +60,6 @@
 skeleton muscles.      []
 %skeleton.             []
 
-* testsuite.
-** tests/reduce.at     [ok]
+* testsuite
 ** tests/pure-parser.at        []
 New tests.
Index: doc/bison.texinfo
--- doc/bison.texinfo Sat, 22 Dec 2001 17:58:53 +0100 akim
+++ doc/bison.texinfo Sat, 29 Dec 2001 09:00:20 +0100 akim
@@ -676,12 +676,13 @@ @node Bison Parser
 expressions.  As it does this, it runs the actions for the grammar rules it
 uses.
 
-The tokens come from a function called the @dfn{lexical analyzer} that you
-must supply in some fashion (such as by writing it in C).  The Bison parser
-calls the lexical analyzer each time it wants a new token.  It doesn't know
-what is ``inside'' the tokens (though their semantic values may reflect
-this).  Typically the lexical analyzer makes the tokens by parsing
-characters of text, but Bison does not depend on this.  @xref{Lexical, ,The 
Lexical Analyzer Function @code{yylex}}.
+The tokens come from a function called the @dfn{lexical analyzer} that
+you must supply in some fashion (such as by writing it in C).  The Bison
+parser calls the lexical analyzer each time it wants a new token.  It
+doesn't know what is ``inside'' the tokens (though their semantic values
+may reflect this).  Typically the lexical analyzer makes the tokens by
+parsing characters of text, but Bison does not depend on this.
address@hidden, ,The Lexical Analyzer Function @code{yylex}}.
 
 The Bison parser file is C code which defines a function named
 @code{yyparse} which implements that grammar.  This function does not make
@@ -722,15 +723,16 @@ @node Stages
 @enumerate
 @item
 Formally specify the grammar in a form recognized by Bison
-(@pxref{Grammar File, ,Bison Grammar Files}).  For each grammatical rule in 
the language,
-describe the action that is to be taken when an instance of that rule
-is recognized.  The action is described by a sequence of C statements.
+(@pxref{Grammar File, ,Bison Grammar Files}).  For each grammatical rule
+in the language, describe the action that is to be taken when an
+instance of that rule is recognized.  The action is described by a
+sequence of C statements.
 
 @item
-Write a lexical analyzer to process input and pass tokens to the
-parser.  The lexical analyzer may be written by hand in C
-(@pxref{Lexical, ,The Lexical Analyzer Function @code{yylex}}).  It could also 
be produced using Lex, but the use
-of Lex is not discussed in this manual.
+Write a lexical analyzer to process input and pass tokens to the parser.
+The lexical analyzer may be written by hand in C (@pxref{Lexical, ,The
+Lexical Analyzer Function @code{yylex}}).  It could also be produced
+using Lex, but the use of Lex is not discussed in this manual.
 
 @item
 Write a controlling function that calls the Bison-produced parser.
@@ -884,9 +886,10 @@ @node Rpcalc Decls
 The @code{#include} directive is used to declare the exponentiation
 function @code{pow}.
 
-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
+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
@@ -1066,9 +1069,10 @@ @node Rpcalc Lexer
 @cindex writing a lexical analyzer
 @cindex lexical analyzer, writing
 
-The lexical analyzer's job is low-level parsing: converting characters or
-sequences of characters into tokens.  The Bison parser gets its tokens by
-calling the lexical analyzer.  @xref{Lexical, ,The Lexical Analyzer Function 
@code{yylex}}.
+The lexical analyzer's job is low-level parsing: converting characters
+or sequences of characters into tokens.  The Bison parser gets its
+tokens by calling the lexical analyzer.  @xref{Lexical, ,The Lexical
+Analyzer Function @code{yylex}}.
 
 Only a simple lexical analyzer is needed for the RPN calculator.  This
 lexical analyzer skips blanks and tabs, then reads in numbers as
@@ -1325,12 +1329,14 @@ exp:      NUM                @{ $$ = $1;
 declarations; the higher the line number of the declaration (lower on
 the page or screen), the higher the precedence.  Hence, exponentiation
 has the highest precedence, unary minus (@code{NEG}) is next, followed
-by @samp{*} and @samp{/}, and so on.  @xref{Precedence, ,Operator Precedence}.
+by @samp{*} and @samp{/}, and so on.  @xref{Precedence, ,Operator
+Precedence}.
 
-The other important new feature is the @code{%prec} in the grammar section
-for the unary minus operator.  The @code{%prec} simply instructs Bison that
-the rule @samp{| '-' exp} has the same precedence as @code{NEG}---in this
-case the next-to-highest.  @xref{Contextual Precedence, ,Context-Dependent 
Precedence}.
+The other important new feature is the @code{%prec} in the grammar
+section for the unary minus operator.  The @code{%prec} simply instructs
+Bison that the rule @samp{| '-' exp} has the same precedence as
address@hidden this case the next-to-highest.  @xref{Contextual
+Precedence, ,Context-Dependent Precedence}.
 
 Here is a sample run of @file{calc.y}:
 
@@ -1683,11 +1689,12 @@ @node Mfcalc Decl
 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
address@hidden 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 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
address@hidden must be declared explicitly so we can specify its value type.
address@hidden Decl, ,Nonterminal Symbols}.
 
 @node Mfcalc Rules
 @subsection Grammar Rules for @code{mfcalc}
@@ -1961,8 +1968,8 @@ @node Mfcalc Symtab
 @end smallexample
 
 This program is both powerful and flexible. You may easily add new
-functions, and it is a simple job to modify this code to install predefined
-variables such as @code{pi} or @code{e} as well.
+functions, and it is a simple job to modify this code to install
+predefined variables such as @code{pi} or @code{e} as well.
 
 @node Exercises
 @section Exercises
@@ -2425,7 +2432,8 @@ @node Multiple Types
 @itemize @bullet
 @item
 Specify the entire collection of possible data types, with the
address@hidden Bison declaration (@pxref{Union Decl, ,The Collection of Value 
Types}).
address@hidden Bison declaration (@pxref{Union Decl, ,The Collection of
+Value Types}).
 
 @item
 Choose one of those types for each symbol (terminal or nonterminal) for
@@ -2447,10 +2455,11 @@ @node Actions
 semantic values associated with tokens or smaller groupings.
 
 An action consists of C statements surrounded by braces, much like a
-compound statement in C.  It can be placed at any position in the rule; it
-is executed at that position.  Most rules have just one action at the end
-of the rule, following all the components.  Actions in the middle of a rule
-are tricky and used only for special purposes (@pxref{Mid-Rule Actions, 
,Actions in Mid-Rule}).
+compound statement in C.  It can be placed at any position in the rule;
+it is executed at that position.  Most rules have just one action at the
+end of the rule, following all the components.  Actions in the middle of
+a rule are tricky and used only for special purposes (@pxref{Mid-Rule
+Actions, ,Actions in Mid-Rule}).
 
 The C code in an action can refer to the semantic values of the components
 matched by the rule with the construct @address@hidden, which stands for
@@ -2730,8 +2739,8 @@ @node Locations
 
 @c (terminal or not) ?
 
-The way locations are handled is defined by providing a data type, and actions
-to take when rules are matched.
+The way locations are handled is defined by providing a data type, and
+actions to take when rules are matched.
 
 @menu
 * Location Type::               Specifying a data type for locations.
@@ -2832,11 +2841,11 @@ @node Location Default Action
 @subsection Default Action for Locations
 @vindex YYLLOC_DEFAULT
 
-Actually, actions are not the best place to compute locations. Since locations
-are much more general than semantic values, there is room in the output parser
-to redefine the default action to take for each rule. The
address@hidden macro is called each time a rule is matched, before the
-associated action is run.
+Actually, actions are not the best place to compute locations. Since
+locations are much more general than semantic values, there is room in
+the output parser to redefine the default action to take for each
+rule. The @code{YYLLOC_DEFAULT} macro is invoked each time a rule is
+matched, before the associated action is run.
 
 Most of the time, this macro is general enough to suppress location
 dedicated code from semantic actions.
@@ -2888,7 +2897,8 @@ @node Declarations
 
 The first rule in the file also specifies the start symbol, by default.
 If you want some other symbol to be the start symbol, you must declare
-it explicitly (@pxref{Language and Grammar, ,Languages and Context-Free 
Grammars}).
+it explicitly (@pxref{Language and Grammar, ,Languages and Context-Free
+Grammars}).
 
 @menu
 * Token Decl::        Declaring terminal symbols.
@@ -2937,7 +2947,8 @@ @node Token Decl
 
 In the event that the stack type is a union, you must augment the
 @code{%token} or other token declaration to include the data type
-alternative delimited by angle-brackets (@pxref{Multiple Types, ,More Than One 
Value Type}).
+alternative delimited by angle-brackets (@pxref{Multiple Types, ,More
+Than One Value Type}).
 
 For example:
 
@@ -2984,7 +2995,8 @@ @node Precedence Decl
 Use the @code{%left}, @code{%right} or @code{%nonassoc} declaration to
 declare a token and specify its precedence and associativity, all at
 once.  These are called @dfn{precedence declarations}.
address@hidden, ,Operator Precedence}, for general information on operator 
precedence.
address@hidden, ,Operator Precedence}, for general information on
+operator precedence.
 
 The syntax of a precedence declaration is the same as that of
 @code{%token}: either
@@ -3071,11 +3083,12 @@ @node Type Decl
 @end example
 
 @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 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.
+Here @var{nonterminal} is the name of a nonterminal symbol, and
address@hidden is the name given in the @code{%union} to the alternative
+that you want (@pxref{Union Decl, ,The Collection of Value Types}).  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.
 
 You can also declare the value type of a terminal symbol.  To do this,
 use the same @code{<@var{type}>} construction in a declaration for the
@@ -3378,10 +3391,10 @@ @node Multiple Parsers
 between different definitions of @code{yyparse}, @code{yylval}, and so on.
 
 The easy way to do this is to use the option @samp{-p @var{prefix}}
-(@pxref{Invocation, ,Invoking Bison}).  This renames the interface functions 
and
-variables of the Bison parser to start with @var{prefix} instead of
address@hidden  You can use this to give each parser distinct names that do
-not conflict.
+(@pxref{Invocation, ,Invoking Bison}).  This renames the interface
+functions and variables of the Bison parser to start with @var{prefix}
+instead of @samp{yy}.  You can use this to give each parser distinct
+names that do not conflict.
 
 The precise list of symbols renamed is @code{yyparse}, @code{yylex},
 @code{yyerror}, @code{yynerrs}, @code{yylval}, @code{yychar} and
@@ -3575,9 +3588,10 @@ @node Token Values
 @end example
 
 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 must use the proper member of the union.
-If the @code{%union} declaration looks like this:
+made from the @code{%union} declaration (@pxref{Union Decl, ,The
+Collection of Value Types}).  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:
 
 @example
 @group
@@ -3786,8 +3800,8 @@ @node Error Reporting
 @vindex yynerrs
 The variable @code{yynerrs} contains the number of syntax errors
 encountered so far.  Normally this variable is global; but if you
-request a pure parser (@pxref{Pure Decl, ,A Pure (Reentrant) Parser}) then it 
is a local variable
-which only the actions can access.
+request a pure parser (@pxref{Pure Decl, ,A Pure (Reentrant) Parser})
+then it is a local variable which only the actions can access.
 
 @node Action Features
 @section Special Features for Use in Actions
@@ -3808,7 +3822,8 @@ @node Action Features
 
 @item $<@var{typealt}>$
 Like @code{$$} but specifies alternative @var{typealt} in the union
-specified by the @code{%union} declaration.  @xref{Action Types, ,Data Types 
of Values in Actions}.
+specified by the @code{%union} declaration.  @xref{Action Types, ,Data
+Types of Values in Actions}.
 
 @item $<@var{typealt}>@var{n}
 Like @address@hidden but specifies alternative @var{typealt} in the
@@ -4237,18 +4252,19 @@ @node How Precedence
 
 The first effect of the precedence declarations is to assign precedence
 levels to the terminal symbols declared.  The second effect is to assign
-precedence levels to certain rules: each rule gets its precedence from the
-last terminal symbol mentioned in the components.  (You can also specify
-explicitly the precedence of a rule.  @xref{Contextual Precedence, 
,Context-Dependent Precedence}.)
-
-Finally, the resolution of conflicts works by comparing the
-precedence of the rule being considered with that of the
-look-ahead token.  If the token's precedence is higher, the
-choice is to shift.  If the rule's precedence is higher, the
-choice is to reduce.  If they have equal precedence, the choice
-is made based on the associativity of that precedence level.  The
-verbose output file made by @samp{-v} (@pxref{Invocation, ,Invoking Bison}) 
says
-how each conflict was resolved.
+precedence levels to certain rules: each rule gets its precedence from
+the last terminal symbol mentioned in the components.  (You can also
+specify explicitly the precedence of a rule.  @xref{Contextual
+Precedence, ,Context-Dependent Precedence}.)
+
+Finally, the resolution of conflicts works by comparing the precedence
+of the rule being considered with that of the look-ahead token.  If the
+token's precedence is higher, the choice is to shift.  If the rule's
+precedence is higher, the choice is to reduce.  If they have equal
+precedence, the choice is made based on the associativity of that
+precedence level.  The verbose output file made by @samp{-v}
+(@pxref{Invocation, ,Invoking Bison}) says how each conflict was
+resolved.
 
 Not all rules and not all tokens have precedence.  If either the rule or
 the look-ahead token has no precedence, then the default is to shift.
@@ -4966,13 +4982,14 @@ @node Debugging
 @end itemize
 
 To make sense of this information, it helps to refer to the listing file
-produced by the Bison @samp{-v} option (@pxref{Invocation, ,Invoking Bison}).  
This file
-shows the meaning of each state in terms of positions in various rules, and
-also what each state will do with each possible input token.  As you read
-the successive trace messages, you can see that the parser is functioning
-according to its specification in the listing file.  Eventually you will
-arrive at the place where something undesirable happens, and you will see
-which parts of the grammar are to blame.
+produced by the Bison @samp{-v} option (@pxref{Invocation, ,Invoking
+Bison}).  This file shows the meaning of each state in terms of
+positions in various rules, and also what each state will do with each
+possible input token.  As you read the successive trace messages, you
+can see that the parser is functioning according to its specification in
+the listing file.  Eventually you will arrive at the place where
+something undesirable happens, and you will see which parts of the
+grammar are to blame.
 
 The parser file is a C program and you can use C debuggers on it, but it's
 not easy to interpret what it is doing.  The parser function is a
@@ -5378,8 +5395,9 @@ @node Table of Symbols
 Reporting Function @code{yyerror}}.
 
 @item yylex
-User-supplied lexical analyzer function, called with no arguments
-to get the next token.  @xref{Lexical, ,The Lexical Analyzer Function 
@code{yylex}}.
+User-supplied lexical analyzer function, called with no arguments to get
+the next token.  @xref{Lexical, ,The Lexical Analyzer Function
address@hidden
 
 @item yylval
 External variable in which @code{yylex} should place the semantic
@@ -5455,7 +5473,8 @@ @node Table of Symbols
 @xref{Precedence Decl, ,Operator Precedence}.
 
 @item %start
-Bison declaration to specify the start symbol.  @xref{Start Decl, ,The 
Start-Symbol}.
+Bison declaration to specify the start symbol.  @xref{Start Decl, ,The
+Start-Symbol}.
 
 @item %token
 Bison declaration to declare token(s) without specifying precedence.
@@ -5466,7 +5485,8 @@ @node Table of Symbols
 @xref{Decl Summary}.
 
 @item %type
-Bison declaration to declare nonterminals.  @xref{Type Decl, ,Nonterminal 
Symbols}.
+Bison declaration to declare nonterminals.  @xref{Type Decl,
+,Nonterminal Symbols}.
 
 @item %union
 Bison declaration to specify several possible data types for semantic



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