We just haven't needed one so far. Can a RdrName and a Name have the same Unique? Well, of course that just depends on what you are using the RdrName Uniques for. It's not a question that has a yes or no answer. Does it matter if (Orig m x) and (Orig n x) have the same Unique? Same answer, except that I bet the answer is "yes it matters". FWIW the "OrigNameCache" is a finite map keyed by (ModuleName,Orig) pairs. Simon | -----Original Message----- | From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On Behalf Of Jan | Stolarek | Sent: 16 June 2014 12:45 | To: ghc-devs@haskell.org | Subject: Uniquable RdrName instance | | Hi all, | | I just found myself in the need of Uniquable instance for RdrName. I'm | surprised that such instance does not exist already because other | datatypes like Name or OccName already have Uniquable instances. So, is | there a reason why Uniquable instance for RdrName does not exist already | (other than "it wasn't needed")? How should such an instance look like? | I made an | attempt: | | rdrNameUnique :: RdrName -> Unique | rdrNameUnique (Unqual occName) = getUnique occName rdrNameUnique (Qual _ | occName) = getUnique occName rdrNameUnique (Orig _ occName) = getUnique | occName | rdrNameUnique (Exact name ) = getUnique name | | But I suspect this might be wrong: | - cases 1 and 4 simply return a Unique for the OccName/Name stored | inside RdrName. I think this will assign the same Unique to RdrName and | corresponding OccName/Name. Is this allowed? | - cases 2 and 3 ignore the Module stored inside RdrName. Again, this | assigns the RdrName with a Unique identical to OccNames stored inside | it. | | Help appreciated. | | Janek | _______________________________________________ | ghc-devs mailing list | ghc-devs@haskell.org | http://www.haskell.org/mailman/listinfo/ghc-devs