#14061: reflection -------------------------------------+------------------------------------- Reporter: zaoqi | Owner: (none) Type: feature request | Status: new Priority: normal | Milestone: Component: Runtime System | Version: 8.0.2 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: | -------------------------------------+------------------------------------- Comment (by AntC): Replying to [comment:3 zaoqi]:
Reflection
The approach in ticket:14004#comment:8 uses reflection. In the code, the line: {{{ | Just HRefl <- ra `eqTypeRep` rb = a == b }}} For `Just HRefl`, the `Refl` is reflection. (Defined in base library `Data.Type.Equality`) This is advanced Haskell. It is very unlikely you need this. Your questions are at beginner level, so it would not help you to just copy the code. You have not explained why you cannot change the definition of `Dyn`. I have put out a request for some Chinese speaking Haskellers to try to help you. I hope they will contact you soon. (Apologies to the GHC team in advance: you might see Chinese text on this ticket.) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14061#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler