(I am currently not on this list, so replies, please cc me.)

The later versions of the GNU parser generator Bison, like ftp://ftp.gnu.org/gnu/bison/bison-1.75.tar.gz (959 KB) ftp://ftp.gnu.org/gnu/bison/bison-1.75.tar.bz2 (759 KB) use the macro processing program M4 to produce the source code output.

This should make it real easy to write parser generator (skeleton) files designed for special languages.

So I wonder if somebody may want to make an attempt to produce such skeleton files for Haskell. Bison has now not only an LALR(1) parser algorithm, but also a GLR parser, and more is to come.

Note that Happy has support for some Haskellish things which you won't get if you use bison to generate Haskell. For example: type signatures on productions, and support for threading a monad around the parser. Nevertheless, doing this sounds entirely feasible. The parser tables generated by bison are very similar to those generated by Happy (I peeked at bison's source when I wrote the table-generation code in Happy), so looking at Happy's LALR(1) machine might be a good place to start. Cheers, Simon