On Wed, 28 Apr 2010, Ivan Miljenovic wrote:
So you don't want the labels to be part of the actual datatype? And for users to then have to deal with any labels they want themselves?
Recently I wrote cabal-sort using FGL http://hackage.haskell.org/package/cabal-sort It sorts cabal packages topologically according to their dependencies. However, I was neither happy with the way FGL currently works, nor with the way I proposed recently (splitting into unlabelled and labelled graphs). I like to use the package name as node identifier. I do not need any label, but I need a node type different from Int. With current FGL I need to maintain a Map PkgName Int. Would it be sensible to generalize the Node type to any Ord type or does FGL use optimizations specific to Int? In another example I used FGL for finding all topological orderings of a set of database transactions. In this case I used an enumeration type as node type. Are there other applications for alternative Node types?