X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/959e5f515a22942a4910ada629ee98540d90d940..69ce078b8cf61eb5087b91538d79a1143ce77c46:/TODO?ds=sidebyside diff --git a/TODO b/TODO index 1bc0e85e..a44f64ec 100644 --- a/TODO +++ b/TODO @@ -12,24 +12,22 @@ 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. - - * 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 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. @@ -52,14 +50,7 @@ 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 +60,21 @@ 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 @@ -81,7 +87,6 @@ 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 @@ -118,6 +123,20 @@ 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 @@ -161,7 +180,7 @@ 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. @@ -179,7 +198,9 @@ Paul notes: PDP-10 ports :-) but they should probably be documented somewhere. - + More importantly, Bison does not currently allow NUL bytes in + tokens, either via escapes (e.g., "x\0y") or via a NUL byte in + the source code. This should get fixed. * --graph Show reductions. [] @@ -324,7 +345,7 @@ 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. @@ -340,5 +361,5 @@ 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., 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. +the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, USA.