Ivan Miljenovic wrote: > (a primitive Sudoku solver, to be precise) Concerning Sudoku, there is a beautiful talk from R. Bird
http://icfp06.cs.uchicago.edu/bird-talk.pdf > The other problem with using a list of lists is that the only reason I'm sure > that the matrix is valid (i.e. all the rows are the same length, etc.) > is because I created it that way, not because the data structure > requires it. You can use nested data types in order to ensure squareness, see also C. Okasaki. From Fast Exponentiation to Square Matrices: An Adventure in Types http://www.eecs.usma.edu/webs/people/okasaki/pubs.html#icfp99 Regards, apfelmus _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe