[ngRepeat:dupes] Duplicates in a repeater are not allowed. Use 'track by' expression to specify uniq

angularjs 使用ng-repeat报错

<div ng-init="words = ['高校','高校','高校']" ng-repeat="word in words">
    {{word}}
</div>

[ngRepeat:dupes] Duplicates in a repeater are not allowed. Use 'track by' expression to specify unique keys

发现是因为相同的内容重复引起，解决方案

<div ng-init="words = ['高校','高校','高校']" ng-repeat="word in words track by $index">
    {{word}}
</div>

在ng-repeat后面加上

track by $index