在这种情况下如何撰写

时间:2019-04-24 09:35:05

标签: javascript functional-programming ramda.js

var articles = [
  {
    title: 'Everything Sucks',
    author: { name: 'Debbie Downer' }
  },
  {
    title: 'If You Please',
    author: { name: 'Caspar Milquetoast' }
  }
];

var names = _.map(_.compose(_.get('name'), _.get('author'))) 
// returning ['Debbie Downer', 'Caspar Milquetoast']

现在,根据上述给定的articles和函数names,创建一个布尔函数,该函数说明给定的人是否写了任何文章。

isAuthor('New Guy', articles) //false
isAuthor('Debbie Downer', articles)//true

我在下面的尝试

var isAuthor = (name, articles) => {
    return _.compose(_.contains(name), names(articles))
};

但是它在jsbin上失败,并显示以下错误。也许有人可以尝试解释我的尝试出了什么问题,以便我可以从错误中学习

  

未捕获的期望假等于函数(n,t){返回r.apply(this,arguments)}

1 个答案:

答案 0 :(得分:1)

Compose返回一个函数,因此您需要将articles传递给该函数。 Compose会将articles传递给getNames,并将getNames的结果传递给contains(name)(还会返回一个函数),该结果将处理作者姓名,并返回布尔result

const { map, path, compose, contains } = R

const getNames = map(path(['author', 'name']))

const isAuthor = (name) => compose(
  contains(name),
  getNames
)

const articles = [{"title":"Everything Sucks","author":{"name":"Debbie Downer"}},{"title":"If You Please","author":{"name":"Caspar Milquetoast"}}]

console.log(isAuthor('New Guy')(articles)) //false
console.log(isAuthor('Debbie Downer')(articles)) //true
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