The source project of this merge request has been removed.
Avoid Data.List.{head,tail}
CLC has approved the proposal to add {-# WARNING #-} to Data.List.{head,tail} (https://github.com/haskell/core-libraries-committee/issues/87). It means that usage of head and tail will emit compile-time warnings.
This patch eliminates the only usage of tail in hpc.