X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/948be909e9a2f63037190428a6bc54b287ebf79d..52f32190aa3e60eb079f8e374cf683094c5529ad:/TODO diff --git a/TODO b/TODO index b21ed19f..168b4e03 100644 --- a/TODO +++ b/TODO @@ -1,31 +1,28 @@ -*- outline -*- -* URGENT: Documenting C++ output -Write a first documentation for C++ output. +* Header guards +From Franc,ois: should we keep the directory part in the CPP guard? -* Documentation -Before releasing, make sure the documentation refers to the current -`output' format. +* Yacc.c: CPP Macros -* Error messages -Some are really funky. For instance +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...). - 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 @@ -55,10 +52,40 @@ 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 @@ -81,6 +108,17 @@ 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? + + * Unit rules Maybe we could expand unit rules, i.e., transform @@ -110,11 +148,22 @@ Are there any Texinfo standards for bibliography? * Java, Fortran, etc. - Add support for languages other than C and C++. Here is a proposed - patch for Java: +** 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 @@ -136,21 +185,11 @@ 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. [] @@ -166,13 +205,12 @@ 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 @@ -286,7 +324,7 @@ the parser with a means to create the (visual) parse tree. ----- -Copyright (C) 2001, 2002 Free Software Foundation, Inc. +Copyright (C) 2001, 2002, 2003 Free Software Foundation, Inc. This file is part of GNU Bison.