I have added the permutation parsers from uulib to uu-parsinglib: http://hackage.haskell.org/packages/archive/uu-parsinglib/2.5.1.1/doc/html/T..., where you find reference to the paper Doaitse On 22 jun 2010, at 09:24, Stephen Tetley wrote:
Hello
Maybe "permutation trees" are a viable starting point?
See the paper "Parsing Permutation Phrases" which appears to be on CiteSeer.
Some slides are also here - the data type definitions and Functor instance for permutation trees are on page 18 (pdf index page 19): http://www.comlab.ox.ac.uk/jeremy.gibbons/wg21/meeting56/loeh-slides.pdf
An alternative implementation for applicative functors is here: http://hackage.haskell.org/package/action-permutations
Note the use of existentials here is pretty cunning, I didn't get very far the time I attempted to use the technique for my own purposes.
Best wishes
Stephen _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe