isTypePreserving :: TermEdit -> Bool
isTypePreserving e = case e of
  Replace _ Same -> True
  Replace _ Subtype -> True
  _ -> False
isTypePreserving :: TermEdit -> Bool
isTypePreserving e = case e of
  Replace _ Same -> True
  Replace _ Subtype -> True
  _ -> False
isTypePreserving e = case e of
  Replace _ Same -> True
  Replace _ Subtype -> True
  _ -> False