Safe Haskell | None |
---|---|
Language | Haskell2010 |
Documentation
gindex :: SOP f xs -> Int Source #
Compute the structural index of a value of a sum type via its Generic representation e.g.:
>>>
data S = Sa | Sb | Sc deriving (Eq, Show, G.Generic)
>>>
instance Generic S
>>>
gindex $ from Sb
1