X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/5d27808262de3a1759f1ee784be6b0cd2733bac5..fe40b679d799a54447a9eecd84a014f5674f1abb:/TODO diff --git a/TODO b/TODO index b6e1a20a..5807ccdc 100644 --- a/TODO +++ b/TODO @@ -14,13 +14,6 @@ find something clean (not like YYLSP_NEEDED...). * Installation -** Disable installation of yacc. - -Add an option to 'configure' that allows people to install Bison -without installing the yacc wrapper script or the rarely-used little -yacc library required by Posix. This is for people who prefer some -other implementation of yacc. - * Documentation Before releasing, make sure the documentation ("Understanding your parser") refers to the current `output' format. @@ -29,14 +22,11 @@ parser") refers to the current `output' format. ** vector Move to using vector, drop stack.hh. -** I18n -Catch up with yacc.c. - * Report ** GLR How would Paul like to display the conflicted actions? In particular, -what when two reductions are possible on a given look-ahead token, but one is +what when two reductions are possible on a given lookahead token, but one is part of $default. Should we make the two reductions explicit, or just keep $default? See the following point. @@ -56,33 +46,11 @@ Provide better assistance for understanding the conflicts by providing a sample text exhibiting the (LALR) ambiguity. See the paper from DeRemer and Penello: they already provide the algorithm. +** Statically check for potential ambiguities in GLR grammars. See + for an approach. -* Extensions - -** Labeling the symbols -Have a look at the Lemon parser generator: instead of $1, $2 etc. they -can name the values. This is much more pleasant. For instance: - - exp (res): exp (a) '+' exp (b) { $res = $a + $b; }; - -I love this. I have been bitten too often by the removal of the -symbol, and forgetting to shift all the $n to $n-1. If you are -unlucky, it compiles... - -But instead of using $a etc., we can use regular variables. And -instead of using (), I propose to use `:' (again). Paul suggests -supporting `->' in addition to `:' to separate LHS and RHS. In other -words: - - r:exp -> a:exp '+' b:exp { r = a + b; }; - -That requires an significant improvement of the grammar parser. Using -GLR would be nice. It also requires that Bison know the type of the -symbols (which will be useful for %include anyway). So we have some -time before... - -Note that there remains the problem of locations: `@r'? +* Extensions ** $-1 We should find a means to provide an access to values deep in the @@ -151,23 +119,6 @@ Are there any Texinfo standards for bibliography? * Java, Fortran, etc. -** Java - -There are a couple of proposed outputs: - -- BYACC/J - which is based on Byacc. - - -- Bison Java - which is based on Bison. - - -Sebastien Serrurier (serrur_s@epita.fr) is working on this: he is -expected to contact the authors, design the output, and implement it -into Bison. - - * Coding system independence Paul notes: @@ -189,10 +140,9 @@ Paul notes: Show reductions. * Broken options ? -** %no-parser ** %token-table ** Skeleton strategy -Must we keep %no-parser? %token-table? +Must we keep %token-table? * src/print_graph.c Find the best graph parameters. @@ -228,9 +178,6 @@ It is unfortunate that there is a total order for precedence. It makes it impossible to have modular precedence information. We should move to partial orders (sounds like series/parallel orders to me). -This will be possible with a Bison parser for the grammar, as it will -make it much easier to extend the grammar. - ** Correlation b/w precedence and associativity Also, I fail to understand why we have to assign the same associativity to operators with the same precedence. For instance, @@ -310,28 +257,24 @@ at the proper place to bison.simple. Ditto for YYACT_PROLOGUE. I was wondering what you think about adding YYACT_PROLOGUE/EPILOGUE to bison. If you're interested, I'll work on a patch. -* Move to Graphviz -Well, VCG seems really dead. Move to Graphviz instead. Also, equip -the parser with a means to create the (visual) parse tree. +* Better graphics +Equip the parser with a means to create the (visual) parse tree. ----- -Copyright (C) 2001, 2002, 2003, 2004, 2006 Free Software Foundation, -Inc. +Copyright (C) 2001-2004, 2006, 2008-2012 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. -Bison is free software; you can redistribute it and/or modify +This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. -Bison is distributed in the hope that it will be useful, +This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License -along with Bison; see the file COPYING. If not, write to -the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, -Boston, MA 02110-1301, USA. +along with this program. If not, see .