1 反例: 2 function createMicrobrewery(name) { 3   var breweryName; 4   if (name) { 5     breweryName = name; 6   } else { 7     breweryName = 'Hipster Brew Co.'; 8   } 9 }10 正例:11 12 function createMicrobrewery(name) {13   var breweryName = name || 'Hipster Brew Co.'14 }