[Haskell-cafe] A point in favour of -XOverlappingInstances (and -XTypeSynonymInstances)

Token.hs:103:15: Overlapping instances for Show (SourcePos, Tok) arising from a use of `anyToken' at Token.hs:103:15-22 Matching instances: instance (Show a, Show b) => Show (a, b) -- Defined in GHC.Show instance [overlap ok] Show Token -- Defined at Token.hs:(39,0)-(40,23) I was just trying _not_ to show the a of (a,b) -- (c) this sig last receiving data processing entity. Inspect headers for past copyright information. All rights reserved. Unauthorised copying, hiring, renting, public performance and/or broadcasting of this signature prohibited.