code: function prelude(token) {
                token = token.toLowerCase();
  
                var result = '';
                var i = 0;
  
                // special case for i = 0 to avoid '-1' index
                if (token[i] === 'y' && isVowel$1(token[i + 1])) {
                  result += token[i].toUpperCase();
                } else {
                  result += token[i];
                }
  
                for (i = 1; i < token.length; i++) {
                  if ((token[i] === 'u' || token[i] === 'i') && isVowel$1(token[i - 1]) && isVowel$1(token[i + 1])) {
                    result += token[i].toUpperCase();
                  } else if (token[i] === 'y' && (isVowel$1(token[i - 1]) || isVowel$1(token[i + 1]))) {
                    result += token[i].toUpperCase();
                  } else if (token[i] === 'u' && token[i - 1] === 'q') {
                    result += token[i].toUpperCase();
                  } else {
                    result += token[i];
                  }
                }
  
                return result;
              }
docs: Pre-process/prepare words as required by french porter stemmer algorithm
  @param  {String} token Word to be prepared
  @return {String}       Prepared word