_homebrew-installed() {
      type brew &> /dev/null
  }
  
  _pyenv-from-homebrew-installed() {
      brew --prefix pyenv &> /dev/null
  }
  
  FOUND_PYENV=0
  pyenvdirs=("$HOME/.pyenv" "/usr/local/pyenv" "/opt/pyenv")
  if _homebrew-installed && _pyenv-from-homebrew-installed ; then
      pyenvdirs=($(brew --prefix pyenv) "${pyenvdirs[@]}")
  fi
  
  for pyenvdir in "${pyenvdirs[@]}" ; do
      if [ -d $pyenvdir/bin -a $FOUND_PYENV -eq 0 ] ; then
          FOUND_PYENV=1
          export PYENV_ROOT=$pyenvdir
          export PATH=${pyenvdir}/bin:$PATH
          eval "$(pyenv init --no-rehash - zsh)"
  
          function pyenv_prompt_info() {
              echo "$(pyenv version-name)"
          }
      fi
  done
  unset pyenvdir
  
  if [ $FOUND_PYENV -eq 0 ] ; then
      function pyenv_prompt_info() { echo "system: $(python -V 2>&1 | cut -f 2 -d ' ')" }
  fi