Alfonso Acosta wrote:
> 2) Think of a change in the internal representation of signals which
> made polymorphic processes possible. Polymorphic processes don't have
> to
> be necessarily definable by the user. They should be happy enough
> with a few polymorphic primitives (mapSnd would be one of them).
I am not sure if this is applicable to your problem, but in GHC you can wrap
polymorphic values in a newtype using higher-rank polymorphism, like in
newtype WrapId = WrapId { unWrapId :: (forall a. a -> a) } deriving Typeable
You can then use
toDyn . WrapId
to wrap 'id' into a Dynamic and
unWrapId . flip fromDyn (error "wrong type")
to unwrap it.
Cheers
Ben
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