X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/ab7f29f8f9a7ad89b6a3163f913e1ee2b7889223..118d4978839515efa4d6bb4815a774c5c3f947e7:/doc/bison.texinfo

diff --git a/doc/bison.texinfo b/doc/bison.texinfo
index 72d027ac..da10c6bb 100644
--- a/doc/bison.texinfo
+++ b/doc/bison.texinfo
@@ -4023,7 +4023,7 @@ associativity and precedence.  @xref{Precedence Decl, ,Operator
 Precedence}.
 
 You can explicitly specify the numeric code for a token type by appending
-a decimal or hexadecimal integer value in the field immediately
+a nonnegative decimal or hexadecimal integer value in the field immediately
 following the token name:
 
 @example
@@ -4076,6 +4076,16 @@ Once you equate the literal string and the token name, you can use them
 interchangeably in further declarations or the grammar rules.  The
 @code{yylex} function can use the token name or the literal string to
 obtain the token type code number (@pxref{Calling Convention}).
+Syntax error messages passed to @code{yyerror} from the parser will reference
+the literal string instead of the token name.
+
+The token numbered as 0 corresponds to end of file; the following line
+allows for nicer error messages referring to ``end of file'' instead
+of ``$end'':
+
+@example
+%token END 0 "end of file"
+@end example
 
 @node Precedence Decl
 @subsection Operator Precedence
@@ -4543,6 +4553,9 @@ valid grammar.
 @cindex push parser
 @findex %define api.push_pull
 
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 A pull parser is called once and it takes control until all its input
 is completely parsed.  A push parser, on the other hand, is called
 each time a new token is made available.
@@ -4872,6 +4885,8 @@ Some of the accepted @var{variable}s are:
 
 @item Purpose: Requests a pull parser, a push parser, or both.
 @xref{Push Decl, ,A Push Parser}.
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
 
 @item Accepted Values: @code{"pull"}, @code{"push"}, @code{"both"}
 
@@ -5032,7 +5047,7 @@ chosen as if the input file were named @file{@var{prefix}.y}.
 
 @deffn {Directive} %language "@var{language}"
 Specify the programming language for the generated parser.  Currently
-supported languages include C and C++.
+supported languages include C, C++, and Java.
 @var{language} is case-insensitive.
 @end deffn
 
@@ -5294,6 +5309,9 @@ exp: @dots{}    @{ @dots{}; *randomness += 1; @dots{} @}
 @section The Push Parser Function @code{yypush_parse}
 @findex yypush_parse
 
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 You call the function @code{yypush_parse} to parse a single token.  This
 function is available if either the @code{%define api.push_pull "push"} or
 @code{%define api.push_pull "both"} declaration is used.
@@ -5309,6 +5327,9 @@ is required to finish parsing the grammar.
 @section The Pull Parser Function @code{yypull_parse}
 @findex yypull_parse
 
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 You call the function @code{yypull_parse} to parse the rest of the input
 stream.  This function is available if the @code{%define api.push_pull "both"}
 declaration is used.
@@ -5322,6 +5343,9 @@ The value returned by @code{yypull_parse} is the same as for @code{yyparse}.
 @section The Parser Create Function @code{yystate_new}
 @findex yypstate_new
 
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 You call the function @code{yypstate_new} to create a new parser instance.
 This function is available if either the @code{%define api.push_pull "push"} or
 @code{%define api.push_pull "both"} declaration is used.
@@ -5329,13 +5353,18 @@ This function is available if either the @code{%define api.push_pull "push"} or
 
 @deftypefun yypstate *yypstate_new (void)
 The fuction will return a valid parser instance if there was memory available
-or NULL if no memory was available.
+or 0 if no memory was available.
+In impure mode, it will also return 0 if a parser instance is currently
+allocated.
 @end deftypefun
 
 @node Parser Delete Function
 @section The Parser Delete Function @code{yystate_delete}
 @findex yypstate_delete
 
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 You call the function @code{yypstate_delete} to delete a parser instance.
 function is available if either the @code{%define api.push_pull "push"} or
 @code{%define api.push_pull "both"} declaration is used.
@@ -7747,6 +7776,46 @@ traditional Yacc grammars.  If your grammar uses a Bison extension
 like @samp{%glr-parser}, Bison might not be Yacc-compatible even if
 this option is specified.
 
+@item -W
+@itemx --warnings
+Output warnings falling in @var{category}.  @var{category} can be one
+of:
+@table @code
+@item midrule-values
+Warn about about mid-rule values that are set but not used within any of
+the actions of the parent rule.  For example, Bison warns about unused
+@code{$2} in:
+
+@example
+exp: '1' @{ $$ = 1; @} '+' exp @{ $$ = $1 + $4; @};
+@end example
+
+It also warns about mid-rule values that are used but not set.  For
+example, Bison warns about unset @code{$$} in the mid-rule action in:
+
+@example
+ exp: '1' @{ $1 = 1; @} '+' exp @{ $$ = $2 + $4; @};
+@end example
+
+These warnings are not enabled by default since they sometimes prove to
+be false alarms in existing grammars employing the Yacc constructs
+@code{$0} or @code{$-@var{b}} (where @var{n} is some positive integer).
+
+
+@item yacc
+Incompatibilities with @acronym{POSIX} Yacc.
+
+@item all
+all the warnings
+@item none
+turn off all the warnings
+@item error
+treat warnings as errors
+@end table
+
+A category can be turned off by prefixing its name with @samp{no-}.  For
+instance, @option{-Wno-syntax} will hide the warnings about unused
+variables.
 @end table
 
 @noindent
@@ -7763,7 +7832,7 @@ already defined, so that the debugging facilities are compiled.
 @itemx --language=@var{language}
 Specify the programming language for the generated parser, as if
 @code{%language} was specified (@pxref{Decl Summary, , Bison Declaration
-Summary}).  Currently supported languages include C and C++.
+Summary}).  Currently supported languages include C, C++, and Java.
 @var{language} is case-insensitive.
 
 @item --locations
@@ -7864,9 +7933,18 @@ If the grammar file is @file{foo.y}, the output file will
 be @file{foo.dot}.
 
 @item --graph=@var{graph-file}
-The behavior of @var{--graph} is the same than @samp{-g}.  The only
+The behavior of @var{--graph} is the same as @samp{-g}.  The only
 difference is that it has an optional argument which is the name of
 the output graph file.
+
+@item -x
+@itemx --xml=@var{file}
+Output an XML report of the @acronym{LALR}(1) automaton computed by Bison.
+@code{=@var{file}} is optional.
+If omitted and the grammar file is @file{foo.y}, the output file will be
+@file{foo.xml}.
+(The current XML schema is experimental and may evolve.
+More user feedback will help to stabilize it.)
 @end table
 
 @node Option Cross Key
@@ -8657,6 +8735,9 @@ main (int argc, char *argv[])
 @c - %language "Java"
 @c - initial action
 
+(The current Java interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
+
 The Java parser skeletons are selected using a language directive,
 @samp{%language "Java"}, or the synonymous command-line option
 @option{--language=java}.
@@ -9769,6 +9850,8 @@ The function to delete a parser instance, produced by Bison in push mode;
 call this function to delete the memory associated with a parser.
 @xref{Parser Delete Function, ,The Parser Delete Function
 @code{yypstate_delete}}.
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
 @end deffn
 
 @deffn {Function} yypstate_new
@@ -9776,6 +9859,8 @@ The function to create a parser instance, produced by Bison in push mode;
 call this function to create a new parser.
 @xref{Parser Create Function, ,The Parser Create Function
 @code{yypstate_new}}.
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
 @end deffn
 
 @deffn {Function} yypull_parse
@@ -9783,12 +9868,16 @@ The parser function produced by Bison in push mode; call this function to
 parse the rest of the input stream.
 @xref{Pull Parser Function, ,The Pull Parser Function
 @code{yypull_parse}}.
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
 @end deffn
 
 @deffn {Function} yypush_parse
 The parser function produced by Bison in push mode; call this function to
 parse a single token.  @xref{Push Parser Function, ,The Push Parser Function
 @code{yypush_parse}}.
+(The current push parsing interface is experimental and may evolve.
+More user feedback will help to stabilize it.)
 @end deffn
 
 @deffn {Macro} YYPARSE_PARAM