Version 1.0 is available upstream. Please consider updating!
It seems that version 1.0 is available upstream, while the latest version in the Gentoo tree is 0.8.0.7. You think this warning is false? Read more about it here.
Differences lists: a list-like type supporting O(1) append.
This is particularly useful for efficient logging and pretty
printing, (e.g. with the Writer monad), where list append
quickly becomes too expensive.