/usr/lib/ghc-doc/hoogle/wai.txt is in libghc-wai-doc 1.4.0.2-1build3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-wai-doc/html/wai.txt
/usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-wai-doc/html/wai.txt