text: (function () {
    'use strict';
  
    /**
     * Filter `an`, used to format singular indefinite article.
     */
    angular.module('frontend.core.filters')
      .filter('an', an);
  
    an.$inject = ['_'];
  
    function an(_) {
      return function (nextWord) {
        if (typeof nextWord !== 'string') {
          return nextWord;
        }
        if (!nextWord) {
          return 'a';
        }
        var vowels = ['a', 'e', 'i', 'o'];
        nextWord = _.trim(nextWord);
        return _.contains(vowels, nextWord[0]) ? 'an' : 'a';
      };
    }
  })();
  