X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/31b850d2d433aff80a6cc31fef79ada95dab0153..5c99151aeb4396bf35b482e27075948c33088afa:/NEWS

diff --git a/NEWS b/NEWS
index aa8c7ea2..d5851390 100644
--- a/NEWS
+++ b/NEWS
@@ -3,7 +3,22 @@ Bison News
 
 * Changes in version ?.? (????-??-??):
 
-** Java skeleton improvements:
+** Additional yylex/yyparse arguments
+
+  The new directive %param declare additional argument to both yylex
+  and yyparse.  The %lex-param, %parse-param, and %param directive
+  support one or more arguments.  Instead of
+
+      %lex-param   {arg1_type *arg1}
+      %lex-param   {arg2_type *arg2}
+      %parse-param {arg1_type *arg1}
+      %parse-param {arg2_type *arg2}
+
+  one may now declare
+
+      %param {arg1_type *arg1} {arg2_type *arg2}
+
+** Java skeleton improvements
 
   The constants for token names were moved to the Lexer interface.
   Also, it is possible to add code to the parser's constructors using
@@ -38,6 +53,31 @@ Bison News
 
 * Changes in version 2.5 (????-??-??):
 
+** Named References Support
+
+  Historically, Yacc and Bison have supported positional references
+  ($n, $$) to allow access to symbol values from inside of semantic
+  actions code.
+
+  Starting from this version, Bison can also accept named references.
+  When no ambiguity is possible, original symbol names may be used
+  as named references:
+
+    if_stmt : 'if' cond_expr 'then' then_stmt ';'
+    { $if_stmt = mk_if_stmt($cond_expr, $then_stmt); }
+
+  In the more common case, explicit names may be declared:
+
+    stmt[res] : 'if' expr[cond] 'then' stmt[then] 'else' stmt[else] ';'
+    { $res = mk_if_stmt($cond, $then, $else); }
+
+  Location information is also accessible using @name syntax.  When
+  accessing symbol names containing dots or dashes, explicit bracketing
+  ($[sym.1]) must be used.
+
+  These features are experimental in this version.  More user feedback
+  will help to stabilize them.
+
 ** IELR(1) and Canonical LR(1) Support
 
   IELR(1) is a minimal LR(1) parser table generation algorithm.  That
@@ -55,9 +95,9 @@ Bison News
   default.  You can specify the type of parser tables in the grammar
   file with these directives:
 
-    %define lr.type "LALR"
-    %define lr.type "IELR"
-    %define lr.type "canonical LR"
+    %define lr.type lalr
+    %define lr.type ielr
+    %define lr.type canonical-lr
 
   The default reduction optimization in the parser tables can also be
   adjusted using `%define lr.default-reductions'.  See the documentation
@@ -68,9 +108,15 @@ Bison News
   These features are experimental.  More user feedback will help to
   stabilize them.
 
-** Multiple %define's for any variable is now an error not a warning.
+** Unrecognized %code qualifiers are now an error not a warning.
+
+** %define improvements.
+
+*** Unrecognized variables are now an error not a warning.
 
-** %define can now be invoked via the command line.
+*** Multiple invocations for any variable is now an error not a warning.
+
+*** Can now be invoked via the command line.
 
   Each of these command-line options
 
@@ -89,7 +135,7 @@ Bison News
   quietly override %define, but -D and --define do not.  For further
   details, see the section "Bison Options" in the Bison manual.
 
-** %define variables renamed.
+*** Variables renamed.
 
   The following %define variables
 
@@ -104,7 +150,18 @@ Bison News
   The old names are now deprecated but will be maintained indefinitely
   for backward compatibility.
 
-** Symbols names
+*** Values no longer need to be quoted in grammar file.
+
+  If a %define value is an identifier, it no longer needs to be placed
+  within quotations marks.  For example,
+
+    %define api.push-pull "push"
+
+  can be rewritten as
+
+    %define api.push-pull push
+
+** Symbol names.
 
   Consistently with directives (such as %error-verbose) and variables
   (e.g. push-pull), symbol names may include dashes in any position,
@@ -133,8 +190,32 @@ Bison News
   about a missing semicolon where it did not before.  Future releases of
   Bison will cease to append semicolons entirely.
 
+** Character literals not of length one.
+
+  Previously, Bison quietly converted all character literals to length
+  one.  For example, without warning, Bison interpreted the operators in
+  the following grammar to be the same token:
+
+    exp: exp '++'
+       | exp '+' exp
+       ;
+
+  Bison now warns when a character literal is not of length one.  In
+  some future release, Bison will report an error instead.
+
+** Verbose error messages fixed for nonassociative tokens.
+
+  When %error-verbose is specified, syntax error messages produced by
+  the generated parser include the unexpected token as well as a list of
+  expected tokens.  Previously, this list erroneously included tokens
+  that would actually induce a syntax error because conflicts for them
+  were resolved with %nonassoc.  Such tokens are now properly omitted
+  from the list.
+
 * Changes in version 2.4.2 (????-??-??):
 
+** Detection of GNU M4 1.4.6 or newer during configure is improved.
+
 ** %code is now a permanent feature.
 
   A traditional Yacc prologue directive is written in the form:
@@ -158,6 +239,12 @@ Bison News
   Bison's Java feature as a whole including its current usage of %code
   is still considered experimental.
 
+** Internationalization.
+
+  Fix a regression introduced in Bison 2.4: Under some circumstances,
+  message translations were not installed although supported by the
+  host system.
+
 * Changes in version 2.4.1 (2008-12-11):
 
 ** In the GLR defines file, unexpanded M4 macros in the yylval and yylloc