Install libghc-gtk2hs-buildtools-doc by entering the following commands in the terminal:
sudo apt update sudo apt install libghc-gtk2hs-buildtools-doc
Description:
gtk2hs-buildtools libraries; documentation
These are modules used by programs build with gtk2hs-buildtools. . This package provides the documentation for a library for the Haskell programming language. See http://www.haskell.org/ for more information on Haskell.
Homepage: http://projects.haskell.org/gtk2hs/
Version: 0.13.3.1-1
Section: universe/doc