import currency from 'currency.js';

var currency1 = currency(1.23);
var currency2 = currency1 + 4.56;
var currency3 = currency2 - 4.56;
var currency4 = currency3 * 2;
var currency5 = currency4 / 4;
var currency6 = currency1 + currency2;

var MultiDecimal = value => currency(value, { decimals: 3 });
var currency7 = MultiDecimal(1.234) + 5.678;

if(currency1 < currency2) { ... }
if(currency1 > currency2) { ... }
if(currency1 === 1.23) { ... }

import currency from 'currency.js';

var currency1 = currency(1.23);
var currency2 = currency1.add(4.56);
var currency3 = currency2.subtract(4.56);
var currency4 = currency3.multiply(2);
var currency5 = currency4.divide(4);
var currency6 = currency1.add(currency2);

var MultiDecimal = value => currency(value, { decimals: 3 });
var currency7 = MultiDecimal(1.234).add(5.678);

if(currency1.value < currency2.value) { ... }
if(currency1.value > currency2.value) { ... }
if(currency1.value === 1.23) { ... }

require("babel-core").transform("code", {
  plugins: ["transform-currency-operators"]
});

import currency from 'currency.js';

export default function myCustomCurrencyDefaults(value) {
  return currency(value, { symbol: '€', ...otherOptions });
}

{
  "plugins": ["transform-currency-operators", ['./path/to/custom/currency']]
}