code: function assignFn(from, to) {
    from = setDefault(10, from);
    to   = setDefault(10, to);
  
    from = numToWord(from);
    to   = capitalize(numToWord(to));
  
    return from + 'To' + to;
  
    // return a copy of a string with its first letter capitalized
    function capitalize(str) {
      return str[0].toUpperCase() + str.slice(1);
    }
  
    // translate a number to its correlating module-specific namespace
    function numToWord(num) {
      num += '';
      switch(num) {
        case '2':
          return 'bin';
        case '8':
          return 'oct';
        case '10':
          return 'dec';
        case '16':
          return 'hex';
        default:
          throw new Error('Base "' + num + '" is not supported');
      }
    }
  
    // if `arg` is not provided, return a default value
    function setDefault(defaultVal, arg) {
      return (typeof arg === 'undefined' ? defaultVal : arg);
    }
  }
docs: Return a property to pass to the 'convert' object
  @param from, [Number], a base to convert from
  @param to, [Number] a base to convert to
  @return, [String] a generated property name
  @throws, an error if the base is not supported by this module