2 Mar
2021
2 Mar
'21
8:08 a.m.
On Tue, 2 Mar 2021, Viktor Dukhovni wrote:
So the intent seems clear, but I don't understand how the instance method definitions are valid. The imports of Both Prelude and Data.Foldable don't include `length` or `null`:
https://github.com/haskell/containers/blob/master/containers/src/Data/Sequen...
It is enough if the method name is imported with qualification. Surprising and maybe inconsistent but that's the state of affairs. GHC even forbids qualification on the left-hand side of a method definition. This at least is consistent with all function definitions.