我可以链接这 2 个“.last”lodash 调用吗？

Question

我有一个带有一系列信用报告历史记录的贷款对象，每个信用报告都有一系列信用评分。我想获取上次信用报告的最后信用评分

let creditReportHistory = loanInfo.creditReportHistory;
let lastReport = creditReportHistory ? _.last(creditReportHistory) : null;
let lastScore = lastReport ? _.last(lastReport.creditScores) : null;
return (
  loanInfo.fico !== null &&          // has a score
  _.isArray(creditReportHistory) &&  // history is an array
  creditReportHistory.length > 0 &&  // at least one credit report
  lastScore === null                 // last report has a last score that is null
);

上面的代码基本上需要知道最后一个report的最后一个score是否为null。其他条件不依赖于 lodash "last()" 调用。

Answer 1

我认为这应该是你的解决方案，但我没有数据集来测试它，所以我只是想复制你的逻辑。

// Your current code:
let creditReportHistory = loanInfo.creditReportHistory;
let lastReport = creditReportHistory ? _.last(creditReportHistory) : null;
let lastScore = lastReport ? _.last(lastReport.creditScores) : null;
return (
  loanInfo.fico !== null &&          // has a score
  _.isArray(creditReportHistory) &&  // history is an array
  creditReportHistory.length > 0 &&  // at least one credit report
  lastScore === null                 // last report has a last score that is null
);

// Updated:
const lastScore = _.chain(loanInfo.creditReportHistory)
  .last()
  .flatMap((lastReport) => lastReport.creditScores)
  .last()
  .value();

return (
  loanInfo.fico !== null
  && lastScore 
);