X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/0fb669f9d648dfdd7a39478a6b658511455ae966..ba7560e26bfa2f5a340545830d46e0437fcb701a:/TODO diff --git a/TODO b/TODO index be43580e..ca610cc0 100644 --- a/TODO +++ b/TODO @@ -12,24 +12,31 @@ They should not: it is not documented. But if they need to, let's find something clean (not like YYLSP_NEEDED...). -* URGENT: Documenting C++ output -Write a first documentation for C++ output. +* 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. +* lalr1.cc +** vector +Move to using vector, drop stack.hh. -* GLR & C++ -Currently, the GLR parser cannot compile with a C++ compiler. - +** 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. @@ -52,14 +59,7 @@ DeRemer and Penello: they already provide the algorithm. * Extensions -** %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 +** 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: @@ -69,6 +69,21 @@ 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'? + + ** $-1 We should find a means to provide an access to values deep in the stack. For instance, instead of @@ -81,32 +96,6 @@ we should be able to have: 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 almost -recommended to yyprint to steal internal variables... - -** Several %unions -I think this is a pleasant (but useless currently) feature, but in the -future, I want a means to %include other bits of grammars, and _then_ -it will be important for the various bits to define their needs in -%union. - -When implementing multiple-%union support, bare the following in mind: - -- when --yacc, this must be flagged as an error. Don't make it fatal - though. - -- The #line must now appear *inside* the definition of yystype. - Something like - - { - #line 12 "foo.y" - int ival; - #line 23 "foo.y" - 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 @@ -197,28 +186,16 @@ Paul notes: the source code. This should get fixed. * --graph -Show reductions. [] +Show reductions. * Broken options ? -** %no-parser [] -** %token-table [] -** Skeleton strategy. [] -Must we keep %no-parser? - %token-table? +** %no-parser +** %token-table +** Skeleton strategy +Must we keep %no-parser? %token-table? * src/print_graph.c -Find the best graph parameters. [] - -* doc/bison.texinfo -** Update -informations about ERROR_VERBOSE. [] -** Add explanations about -skeleton muscles. [] -%skeleton. [] - -* testsuite -** tests/pure-parser.at [] -New tests. +Find the best graph parameters. * BTYacc See if we can integrate backtracking in Bison. Charles-Henri de @@ -333,22 +310,22 @@ 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 Free Software Foundation, Inc. +Copyright (C) 2001, 2002, 2003, 2004, 2006 Free Software Foundation, +Inc. -This file is part of GNU Bison. +This file is part of Bison, the GNU Compiler Compiler. -GNU Bison is free software; you can redistribute it and/or modify +Bison 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. -GNU Bison is distributed in the hope that it will be useful, +Bison 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.