soveran

  $ cat riddle
  Vixen Rudolph
  Vixen Prancer
  Vixen Dasher
  Dancer Vixen
  Comet Vixen
  ...
  Vixen Dasher

  $ tsort riddle
  Dancer
  Donder
  Comet
  Vixen
  Blitzen
  Dasher
  Rudolph
  Cupid
  Prancer

  if [ condition ]; then
    ...
  else
    ...
  fi

  if (condition) {
    ...
  } else {
    ...
  }

  case $1 in
    "bar")
      ... ;;
    "baz")
      ... ;;
  esac

  switch ($1) {
    case "bar"
      ...
    case "baz"
      ...
  }