third_party/angular/docs/examples/example-guide-concepts-21/finance2.js

  angular.module('finance2', [])
    .factory('currencyConverter', function() {
      var currencies = ['USD', 'EUR', 'CNY'];
      var usdToForeignRates = {
        USD: 1,
        EUR: 0.74,
        CNY: 6.09
      };
      var convert = function (amount, inCurr, outCurr) {
        return amount * usdToForeignRates[outCurr] / usdToForeignRates[inCurr];
      };

      return {
        currencies: currencies,
        convert: convert
      };
    });