showDep (Dep is_exe qpn (Constrained [(vr, v)])) =
  showVar v ++ " => " ++ showQPN qpn ++
  (if is_exe then " (exe) " else "") ++ showVR vr
showDep (Dep is_exe qpn (Constrained [(vr, v)])) =
  showVar v ++ " => " ++ showQPN qpn ++
  (if is_exe then " (exe) " else "") ++ showVR vr
showDep (Dep is_exe qpn (Constrained [(vr, v)])) =
  showVar v ++ " => " ++ showQPN qpn ++
  (if is_exe then " (exe) " else "") ++ showVR vr