X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/f414d77d3876f559ac0af33285b9a9235f54a58f..f55ec70868b265324deb269be2059b3f85864ac6:/TODO diff --git a/TODO b/TODO index e33f3aee..4762559e 100644 --- a/TODO +++ b/TODO @@ -2,97 +2,34 @@ * Header guards -En rentrant chez moi, je relance un `make' sur un projet que j'ai avancé -ailleurs durant la semaine. Le système que j'utilise ici est un peu plus -à jour que l'autre, et le Bison est probablement plus récent itou. Ici, -c'est la version 1.33. J'obtiens, en montrant un peu plus que nécessaire: - -----------------------------------------------------------------------> -cd ~/fpub/pyrexpp/Pyrexpp/ -LANGUAGE= /usr/bin/make MAKEFLAGS='-k -j2' -/usr/bin/make -C .. install -make[1]: Entre dans le répertoire `/bpi/titan/home/pinard/fpub/pyrexpp' -install -g bpi -m 2775 -d Prépare-titan -chmod g+sw Prépare-titan -touch Prépare-titan/.estampille -/usr/bin/gcc -fPIC -I/usr/include/python2.2 -IPrépare-titan -g -c -o Prépare-titan/ctools.o ctools.c -bison -d -o Prépare-titan/c-parser.c c-parser.y -/usr/bin/gcc -fPIC -I/usr/include/python2.2 -IPrépare-titan -g -c -o Prépare-titan/c-parser.o Prépare-titan/c-parser.c -flex -t c-scanner.l | grep -v '^#line' > Prépare-titan/c-scanner.c -/usr/bin/gcc -fPIC -I/usr/include/python2.2 -IPrépare-titan -g -c -o Prépare-titan/c-scanner.o Prépare-titan/c-scanner.c -In file included from Prépare-titan/c-scanner.c:547: -Prépare-titan/c-parser.h:1: warning: garbage at end of `#ifndef' argument -Prépare-titan/c-parser.h:2: warning: missing white space after `#define BISON_PR' -/usr/bin/gcc -o Prépare-titan/ctools.so Prépare-titan/ctools.o Prépare-titan/c-scanner.o -shared -lm -python setup.py --quiet build -install -g bpi -m 664 Prépare-titan/ctools.so /bpi/titan/local/lib/python2.2/site-packages/Pyrexpp -python setup.py --quiet install -make[1]: Quitte le répertoire `/bpi/titan/home/pinard/fpub/pyrexpp' -[...] -----------------------------------------------------------------------< - -Diagnostics que je n'avais sûrement pas, plus tôt en journée, sur l'autre -système. En allant voir, je trouve: - -----------------------------------------------------------------------> -#ifndef BISON_PRÉPARE_TITAN_C_PARSER_H -# define BISON_PRÉPARE_TITAN_C_PARSER_H - -# ifndef YYSTYPE -# define YYSTYPE int -# endif -# define IDENTIFIER 257 -[...] - -extern YYSTYPE yylval; - -#endif /* not BISON_PRÉPARE_TITAN_C_PARSER_H */ -----------------------------------------------------------------------< - -Le pré-processeur de C n'est pas à l'aise avec les caractères accentués -dans les identificateurs. - -Bon, de mon expérience, il n'a jamais été nécessaire de protéger un fichier -`.h' de Bison ou Yacc contre de multiples inclusions, mais si ça été -fait, je présume qu'il y avait un problème réel et convaincant à régler, -et qu'il ne s'agit pas d'une simple fantaisie: je ne mettrai donc pas -ça en doute. Mais le choix du nom de l'identificateur laisse à désirer, -tu en conviendras :-). Et faut-il vraiment y inclure le répertoire? +From Franc,ois: should we keep the directory part in the CPP guard? -* URGENT: Documenting C++ output -Write a first documentation for C++ output. +* Yacc.c: CPP Macros - -* Documentation -Before releasing, make sure the documentation refers to the current -`output' format. +Do some people use YYPURE, YYLSP_NEEDED like we do in the test suite? +They should not: it is not documented. But if they need to, let's +find something clean (not like YYLSP_NEEDED...). -* Error messages -Some are really funky. For instance - - type clash (`%s' `%s') on default action - -is really weird. Revisit them all. +* URGENT: Documenting C++ output +Write a first documentation for C++ output. -* read_pipe.c -This is not portable to DOS for instance. Implement a more portable -scheme. Sources of inspiration include GNU diff, and Free Recode. +* Documentation +Before releasing, make sure the documentation ("Understanding your +parser") refers to the current `output' format. -* value_components_used -Was defined but not used: where was it coming from? It can't be to -check if %union is used, since the user is free to $n on her -union, doesn't she? +* GLR & C++ +Currently, the GLR parser cannot compile with a C++ compiler. * Report ** GLR How would Paul like to display the conflicted actions? In particular, -what when two reductions are possible on a given lookahead, but one is +what when two reductions are possible on a given look-ahead token, but one is part of $default. Should we make the two reductions explicit, or just keep $default? See the following point. @@ -115,10 +52,39 @@ DeRemer and Penello: they already provide the algorithm. * Extensions -** yyerror, yysymprint interface +** %destructor +I think we should document it as experimental, and allow its use in +the next releases. But we also need to port it to GLR. What about +lalr1.cc? Well, read what Hans reported, maybe we don't want +%detructor. On the other hand, there is no reason not to provide it: +users can avoid its use. + +** $foo +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... + +** $-1 +We should find a means to provide an access to values deep in the +stack. For instance, instead of + + baz: qux { $$ = $-1 + $0 + $1; } + +we should be able to have: + + foo($foo) bar($bar) baz($bar): qux($qux) { $baz = $foo + $bar + $qux; } + +Or something like this. + +** yysymprint interface It should be improved, in particular when using Bison features such as -locations, and YYPARSE_PARAMS. For the time being, it is recommended -to #define yyerror and yyprint to steal internal variables... +locations, and YYPARSE_PARAMS. For the time being, it is almost +recommended to yyprint to steal internal variables... ** Several %unions I think this is a pleasant (but useless currently) feature, but in the @@ -141,6 +107,31 @@ When implementing multiple-%union support, bare the following in mind: char *sval; } +** %if and the like +It should be possible to have %if/%else/%endif. The implementation is +not clear: should it be lexical or syntactic. Vadim Maslow thinks it +must be in the scanner: we must not parse what is in a switched off +part of %if. Akim Demaille thinks it should be in the parser, so as +to avoid falling into another CPP mistake. + +** -D, --define-muscle NAME=VALUE +To define muscles via cli. Or maybe support directly NAME=VALUE? + +** XML Output +There are couple of available extensions of Bison targeting some XML +output. Some day we should consider including them. One issue is +that they seem to be quite orthogonal to the parsing technique, and +seem to depend mostly on the possibility to have some code triggered +for each reduction. As a matter of fact, such hooks could also be +used to generate the yydebug traces. Some generic scheme probably +exists in there. + +XML output for GNU Bison and gcc + http://www.cs.may.ie/~jpower/Research/bisonXML/ + +XML output for GNU Bison + http://yaxx.sourceforge.net/ + * Unit rules Maybe we could expand unit rules, i.e., transform @@ -183,7 +174,7 @@ There are a couple of proposed outputs: which is based on Bison. -Sébastien Serrurier (serrur_s@epita.fr) is working on this: he is +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. @@ -207,21 +198,11 @@ Paul notes: Show reductions. [] * Broken options ? -** %no-lines [ok] ** %no-parser [] -** %pure-parser [] ** %token-table [] -** Options which could use parse_dquoted_param (). -Maybe transferred in lex.c. -*** %skeleton [ok] -*** %output [] -*** %file-prefix [] -*** %name-prefix [] - ** Skeleton strategy. [] Must we keep %no-parser? %token-table? -*** New skeletons. [] * src/print_graph.c Find the best graph parameters. [] @@ -237,13 +218,12 @@ skeleton muscles. [] ** tests/pure-parser.at [] New tests. -* input synclines -Some users create their foo.y files, and equip them with #line. Bison -should recognize these, and preserve them. - * BTYacc -See if we can integrate backtracking in Bison. Contact the BTYacc -maintainers. +See if we can integrate backtracking in Bison. Charles-Henri de +Boysson is working on this, and already has some +results. Vadim Maslow, the maintainer of BTYacc was contacted, and we +stay in touch with him. Adjusting the Bison grammar parser will be +needed to support some extra BTYacc features. This is less urgent. ** Keeping the conflicted actions First, analyze the differences between byacc and btyacc (I'm referring @@ -357,7 +337,7 @@ the parser with a means to create the (visual) parse tree. ----- -Copyright (C) 2001, 2002 Free Software Foundation, Inc. +Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc. This file is part of GNU Bison.