You can clone with
HTTPS or Subversion.
These programs are required to build or use HSH.
HSH requires GHC 6.6 or above. Due to GHC design limitations, HSH is not compatible with ghci or the GHC threaded runtime.
Hugs does not provide an interface to fork(), which is necessary for HSH to work. HSH is therefore not compatible with Hugs.
You need all of these to build HSH.