anchor.diff:  WORKDIR /home/ghc
   USER ghc
   
  -ENV PATH /opt/ghc/8.0.1/bin:/opt/cabal/1.24/bin:/php/arcanist/bin:$PATH 
  +ENV PATH /opt/ghc/8.2.1/bin:/opt/cabal/1.24/bin:/php/arcanist/bin:$PATH 
   
   # Build dependencies for nofib-analyse
   RUN cabal update && cabal install html regex-compat 
  
positive.code: 
    ## install minimal set of haskell packages
    # from darinmorrison/haskell
    ghc-8.0.1 \
    alex \
    cabal-install-1.24 \
    happy \
  
negative.code: ## add ppa for ubuntu trusty haskell packages
  # from darinmorrison/haskell
  RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F6F88286 \
    && echo 'deb     http://ppa.launchpad.net/hvr/ghc/ubuntu zesty main' >> /etc/apt/sources.list.d/haskell.list \
    && echo 'deb-src http://ppa.launchpad.net/hvr/ghc/ubuntu zesty main' >> /etc/apt/sources.list.d/haskell.list
  
  RUN apt-get update && apt-get install -y \
  
  