Parser and pretty-printer for GML file format.
How to build the node label out of the set of GML attributes. For example
node [ id 12 label "foo" ]
will call this function with ["id", Int 12; "label", String "foo"]
["id", Int 12; "label", String "foo"]
How to build the edge label out of the set of GML attributes
Provide a parser for GML file format.
Signature for graph required by Print. Sub-signature of Sig.G.
Provide a pretty-printer for GML file format.