haskell - How can I create a value with a specific TypeRep -


using data.typeable, can reify type of value -

typeof :: typeable => -> typerep

however, given typerep, there seems no way "set" value type.

for example -

maybeinttype :: typerep maybeinttype = typeof (just 100 :: maybe int)

but how use maybeinttype create (nothing :: maybe int)?


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