formatCurrency, formatting with exponent and currency

format-currency.js

// 20 May 2019
// formatCurrency, i18n 

/**
 * @function formatCurrency accepts an object containing value, currency, and
 * exponent fields, and returns a string containing an currency- and exponent-
 * based value.
 *
 * @param {Number} value
 * @param {Number} exponent
 * @param {String} currency
 *
 * @returns {String} formatted value
 */

function formatCurrency(amount) {
  var n = amount.value / Number('1e' + amount.exponent) || '0'
  var s = (n).toLocaleString({currency: amount.currency});

  return s + ' ' + (amount.currency || '?');
}

[
  {
    value: 1123456,
    currency: 'GBP',
    exponent: 2,
    locale: 'gb-GB'
  },
  {
    value: 987654321,
    currency: 'DINARS',
    exponent: 2,
    locale: 'ar-IQ'
  },
  {
    value: null,
    currency: '',
    exponent: 0,
    locale: ''
  }
].map(function(amount) {
  console.log(formatCurrency(amount))
});

/*
 11,234.56 GBP
 ٩٬٨٧٦٬٥٤٣٫٢١ DINARS
 0 ?
*/

money.js

// 20 May 2019
// currency formatting with exponent and currency

var currencies = {
  USD: '$',
  GBR: '£',
  EUR: '€'
}


function money(amount) {
  var v = Number(amount.value)
  var d = v / Number('1e' + amount.exponent)
  var c = currencies[amount.currency] || amount.currency
  
  return d + ' ' + amount.currency
}


/* test it out */


var tests = [
  {
    value: '6001',
    exponent: '2',
    currency: 'USD'
  },
  {
    value: '16002',
    exponent: '2',
    currency: 'GBR'
  },
  {
    value: '126003',
    exponent: '2',
    currency: 'EUR'
  },
  {
    value: '123456',
    exponent: '3',
    currency: 'فلس'  // dinars
  }
];
  
var results = tests.map(function(test) {
  return money(test)
});
  

console.log(
  JSON.stringify(results, null, 2)
);
  
/*
 [
  "60.01 USD",
  "160.02 GBR",
  "1260.03 EUR",
  "123.456 فلس"
]
*/