Hi Alistair,
http://haskell.org/hoogle/?q=typeOf
C:\>ghci
GHCi, version 6.8.1: http://www.haskell.org/ghc/ :? for help
Loading package base ... linking ... done.
Prelude> :m Data.Typeable
Prelude Data.Typeable> typeOf "neil"
[Char]
Thanks
Neil
On 12/14/07, Alistair Bayley
I've been learning/playing with Data.Generics a bit, and have a how-to question...
dataTypeOf ""
If I say then I get
DataType {tycon = "Prelude.[]", datarep = AlgRep [[],(:)]}
No surprises there. But I'd really like to know that I have a String, or [Char]. How do I get the name of the concrete type that the list contains? Is that a reasonable thing to ask for?
I can say:
gmapQ dataTypeOf "a" to get: [ DataType {tycon = "Prelude.Char", datarep = StringRep} , DataType {tycon = "Prelude.[]", datarep = AlgRep [[],(:)]} ]
But if I say:
gmapQ dataTypeOf "" I get: []
which makes sense when you consider the stucture of the List ADT, but doesn't help me determine the type of the value.
Alistair _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe