[Haskell-beginners] how to make something Typeable, for Data.Dynamic?
Edward Z. Yang
ezyang at MIT.EDU
Mon Apr 4 23:22:15 CEST 2011
You need the language extension DeriveDataTypeable,
and then you just add
to the end of your data declaration.
Excerpts from Rob Nikander's message of Mon Apr 04 17:16:57 -0400 2011:
> Can someone show me a code snippet that would make a simple record
> type Typeable so I can wrap one in a Data.Dynamic? I'm looking at the
> haddock docs and I don't see how to do it. I know to define "typeOf
> :: MyRecord -> TypeRep". But how to make a TypeRep?
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