Install libghc-x509-doc by entering the following commands in the terminal:
sudo apt update sudo apt install libghc-x509-doc
Description:
X.509 reader and writer; documentation
Reads/writes X.509 Certificate, CRLs and their signed equivalents. Follows RFC5280 / RFC6818. . 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://github.com/vincenthz/hs-certificate
Version: 1.7.2-1build4
Section: universe/doc