Install libghc-hoogle-doc by entering the following commands in the terminal:
sudo apt update sudo apt install libghc-hoogle-doc
Description:
Haskell API Search; documentation
Hoogle is a Haskell API search engine, which allows you to search many standard Haskell libraries by either function name, or by approximate type signature. . This package contains the documentation files.
Homepage: http://hoogle.haskell.org/
Version: 5.0.14+dfsg1-1build2
Section: universe/doc