#15167: DerivClause list is not populated for (TyConI (DataD ...)) -------------------------------------+------------------------------------- Reporter: 0xd34df00d | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Template Haskell | Version: 8.4.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * cc: newcomer (added) Comment: Indeed, this is expected. Reified data declarations never have derived instances attached to them, as they're only used when splicing a TH- constructed data type into source code. (If you want to know a data type's instances via TH, you should use `reifyInstances`.) The Haddocks in `template-haskell` currently don't state that reified data types lack derived instance information, however, so it would be good to update the documentation to reflect this. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15167#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler