anchor.diff:  RUN \
         mkdir ~/.rbenv/plugins \
     &&  git clone https://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build \
  -  &&  echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bashrc 
  +  &&  echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' | tee -a ~/.bashrc ~/.profile 
   
   # do not copy gem package documentation
   RUN echo "gem: --no-ri --no-rdoc" > ~/.gemrc
   
   #restart shell
  -RUN exec  ~/.bashrc
  +RUN .  ~/.bashrc
   
   # ENV RBENV_ROOT /usr/local/rbenv
   # ENV PATH $RBENV_ROOT/bin:$RBENV_ROOT/shims:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
  
positive.code: #Install rbenv as rails 
  RUN \
        git clone https://github.com/sstephenson/rbenv.git ~/.rbenv \
    &&  echo 'export PATH="$HOME/.rbenv/bin:$HOME/.rbenv/shims:$PATH"' >> ~/.bashrc \
    &&  echo 'eval "$(rbenv init -)"' >> ~/.bashrc \
    &&  echo 'export PATH="$HOME/.rbenv/bin:/usr/bin:/bin:$PATH"' >> ~/.bashrc 
  
  # Install rbenv plugin: ruby-build for global rbenv installation
  # RUN mkdir /usr/local/rbenv/plugins
  
negative.code: 
  ## Install Rails dependencies
  RUN \
        sudo apt-get install -y software-properties-common  \
    &&  sudo add-apt-repository ppa:chris-lea/node.js  \
    &&  sudo apt-get update  \
    &&  sudo apt-get install -y nodejs  
  