javascript - Lodash 从重复的对象键创建集合

Question

我有以下结构:

var output = [{
    "article": "BlahBlah",
    "title": "Another blah"
}, {
    "article": "BlahBlah",
    "title": "Return of the blah"
}, {
    "article": "BlahBlah2",
    "title": "The blah strikes back"
}, {
    "article": "BlahBlah2",
    "title": "The blahfather"
}]

根据上面使用优雅的 lodash 单行代码，我需要创建以下结构。

var newOutput = [{
    "article": "BlahBlah",
    "titles": ["Another blah", "Return of the blah"]
}, {
   "article": "BlahBlah2",
   "titles": ["The blah strikes back", "The blahfather"]
}]

一如既往的帮助，非常感谢。对于解决方案如何运作的解释，这是一个巨大的优势。

Answer 1

使用_.groupBy然后 _.map结果对象到对象数组。

var newOutput = _(output)
    .groupBy('article')
    .map(function(v, k){ return { article: k, titles: _.map(v, 'title') } })
    .value();

var output = [{"article":"BlahBlah","title":"Another blah"},{"article":"BlahBlah","title":"Return of the blah"},{"article":"BlahBlah2","title":"The blah strikes back"},{"article":"BlahBlah2","title":"The blahfather"}];

let newOutput = _(output)
    .groupBy('article')
    .map(function(v, k){ return { article: k, titles: _.map(v, 'title') } })
    .value();

console.log(newOutput);

<script src="https://cdn.jsdelivr.net/lodash/4.13.1/lodash.min.js"></script>

使用 ES6 箭头函数，

var newOutput = _(output)
    .groupBy('article')
    .map((v, k) => ({ article: k, titles: _.map(v, 'title') }))
    .value();