Missing Data context for non-linear as-patterns
Consider the function f x@(Just _) x = ()
. Its inferred type should be f :: Data a => Maybe a -> Maybe a -> ()
, however, it is f :: Maybe a -> Maybe a -> ()
.
Edited by Finn Teegen
Consider the function f x@(Just _) x = ()
. Its inferred type should be f :: Data a => Maybe a -> Maybe a -> ()
, however, it is f :: Maybe a -> Maybe a -> ()
.