Build the docker image located in docs (it's important you do this from the root of the repo), with
docker build -t hashed-docker -f docs/Dockerfile .
-Then run the docker container to generate the haddock documentation (NOTE: every time you alter the -code base you'll have to rebuild the image)
-docker run -v /some/path:/home/HashedExpression/docs hashed-docker
-this will generate all the haddock documentation (in html) into /some/path on your local system