convertExpr (P.PrefixOperation operator operand) = do
  convertedOperand <- convertExpr operand
  return $ E.PrefixOperation operator convertedOperand
convertExpr (P.PrefixOperation operator operand) = do
  convertedOperand <- convertExpr operand
  return $ E.PrefixOperation operator convertedOperand
convertExpr (P.PrefixOperation operator operand) = do
  convertedOperand <- convertExpr operand
  return $ E.PrefixOperation operator convertedOperand