Undo change made earlier today: it caused autopoint to not bring

[bison.git] / doc / bison.texinfo

diff --git a/doc/bison.texinfo b/doc/bison.texinfo
index c7e1b6338ae9f544bffb0a56e16daab31e0ef12e..f01c638a8802f188db54e2e55c9e9840d608c0e7 100644 (file)
--- a/doc/bison.texinfo
+++ b/doc/bison.texinfo
@@ -44,7 +44,7 @@ This manual is for @acronym{GNU} Bison (version @value{VERSION},
 @value{UPDATED}), the @acronym{GNU} parser generator.
 
 Copyright @copyright{} 1988, 1989, 1990, 1991, 1992, 1993, 1995, 1998,
-1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
 
 @quotation
 Permission is granted to copy, distribute and/or modify this document
@@ -223,7 +223,7 @@ Bison Declarations
 * Union Decl::        Declaring the set of all semantic value types.
 * Type Decl::         Declaring the choice of type for a nonterminal symbol.
 * Destructor Decl::   Declaring how symbols are freed.
-* Expect Decl::       Suppressing warnings about shift/reduce conflicts.
+* Expect Decl::       Suppressing warnings about parsing conflicts.
 * Start Decl::        Specifying the start symbol.
 * Pure Decl::         Requesting a reentrant parser.
 * Decl Summary::      Table of all Bison declarations.
@@ -356,7 +356,7 @@ encourage people to make other software free.  So we decided to make the
 practical conditions for using Bison match the practical conditions for
 using the other @acronym{GNU} tools.
 
-This exception applies only when Bison is generating C code for a
+This exception applies only when Bison is generating C code for an
 @acronym{LALR}(1) parser; otherwise, the @acronym{GPL} terms operate
 as usual.  You can
 tell whether the exception applies to your @samp{.c} output file by
@@ -2338,7 +2338,7 @@ can be done with two @var{Prologue} blocks, one before and one after the
 %@}
 
 %union @{
-  long n;
+  long int n;
   tree t;  /* @r{@code{tree} is defined in @file{ptypes.h}.} */
 @}
 
@@ -2481,7 +2481,8 @@ does not enforce this convention, but if you depart from it, people who
 read your program will be confused.
 
 All the escape sequences used in string literals in C can be used in
-Bison as well.  However, unlike Standard C, trigraphs have no special
+Bison as well, except that you must not use a null character within a
+string literal.  Also, unlike Standard C, trigraphs have no special
 meaning in Bison string literals, nor is backslash-newline allowed.  A
 literal string token must contain two or more characters; for a token
 containing just one character, use a character token (see above).
@@ -2754,7 +2755,7 @@ This macro definition must go in the prologue of the grammar file
 
 In most programs, you will need different data types for different kinds
 of tokens and groupings.  For example, a numeric constant may need type
-@code{int} or @code{long}, while a string constant needs type @code{char *},
+@code{int} or @code{long int}, while a string constant needs type @code{char *},
 and an identifier might need a pointer to an entry in the symbol table.
 
 To use more than one data type for semantic values in one parser, Bison
@@ -3279,7 +3280,7 @@ Grammars}).
 * Union Decl::        Declaring the set of all semantic value types.
 * Type Decl::         Declaring the choice of type for a nonterminal symbol.
 * Destructor Decl::   Declaring how symbols are freed.
-* Expect Decl::       Suppressing warnings about shift/reduce conflicts.
+* Expect Decl::       Suppressing warnings about parsing conflicts.
 * Start Decl::        Specifying the start symbol.
 * Pure Decl::         Requesting a reentrant parser.
 * Decl Summary::      Table of all Bison declarations.
@@ -3308,10 +3309,12 @@ associativity and precedence.  @xref{Precedence Decl, ,Operator
 Precedence}.
 
 You can explicitly specify the numeric code for a token type by appending
-an integer value in the field immediately following the token name:
+a decimal or hexadecimal integer value in the field immediately
+following the token name:
 
 @example
 %token NUM 300
+%token XNUM 0x12d // a GNU extension
 @end example
 
 @noindent
@@ -3557,6 +3560,7 @@ typefull: string;  // $$ = $1 applies, $1 is not destroyed.
 @cindex warnings, preventing
 @cindex conflicts, suppressing warnings of
 @findex %expect
+@findex %expect-rr
 
 Bison normally warns if there are any conflicts in the grammar
 (@pxref{Shift/Reduce, ,Shift/Reduce Conflicts}), but most real grammars
@@ -3577,6 +3581,18 @@ reduce/reduce conflicts.  The usual warning is
 given if there are either more or fewer conflicts, or if there are any
 reduce/reduce conflicts.
 
+For normal LALR(1) parsers, reduce/reduce conflicts are more serious,
+and should be eliminated entirely.  Bison will always report
+reduce/reduce conflicts for these parsers.  With GLR parsers, however,
+both shift/reduce and reduce/reduce are routine (otherwise, there
+would be no need to use GLR parsing).  Therefore, it is also possible
+to specify an expected number of reduce/reduce conflicts in GLR
+parsers, using the declaration:
+
+@example
+%expect-rr @var{n}
+@end example
+
 In general, using @code{%expect} involves these steps:
 
 @itemize @bullet
@@ -6213,7 +6229,7 @@ compatibility with @acronym{POSIX}:
 
 @example
 #! /bin/sh
-bison -y "$@"
+bison -y "$@@"
 @end example
 @end table
 
@@ -6507,6 +6523,11 @@ handle features like include files, you might consider using Flex
 functions like @samp{yy_switch_to_buffer} that manipulate multiple
 input buffers.
 
+If your Flex-generated scanner uses start conditions (@pxref{Start
+conditions, , Start conditions, flex, The Flex Manual}), you might
+also want to reset the scanner's state, i.e., go back to the initial
+start condition, through a call to @samp{BEGIN (0)}.
+
 @node Strings are Destroyed
 @section Strings are Destroyed