úÎôj C is a class that provided a way to reference into a specific type, 1 and a way to map over the deferenced internals. $ takes a data structure that admits , and returns a  that contains 0 the dereferenced nodes, with their children as  rather than recursive values.       data-reify-0.1Data.Unsafe.ReifyGraphMuRefDeRefdeRefmapDeRef reifyGraphbase Data.UniqueUnique findNodeseq