问Javascript对象排序数组使用显式声明，使用变量时中断

EN

const sortedAlbums = allAlbums.sort((a, b) => a.releaseDate - b.releaseDate);
console.log(sortedAlbums);

$.ajax({
  url: 'https://api-marcalencc-metacritic-v1.p.mashape.com/person/drake/album',
  type: 'get',
  dataType: 'json',
  headers: {
    "X-Mashape-Key": "----------------------------",
    "Accept": "application/json"
  },
  success: function(data) {
    handleDiscography(data);
    allAlbums.sort((a, b) => a.releaseDate - b.releaseDate);
    console.log(allAlbums);
  }
})

function Album(releaseDate) {
  this.releaseDate = new Date(releaseDate).getTime();
}


function handleDiscography(data) {
  const album = data[0].CreditMediaPairItems;
  return album.map(val => new Album(val.Item.ReleaseDate))
}

function getAlbumData() {
  return $.ajax({
      url: 'https://api-marcalencc-metacritic-v1.p.mashape.com/person/drake/album',
      type: 'get',
      dataType: 'json',
      headers: {
        "X-Mashape-Key": "----------------------------",
        "Accept": "application/json"
      }
    })
    .then(data => handleDiscography)
}


getAlbumData()
  .then(allAlbums => {
    allAlbums.sort(function(a, b) {
      return a.releaseDate - b.releaseDate;
    });

    console.log(allAlbums)
  })

const allAlbums = [
  {
    'releaseDate': 1461913200000,
    'critic_rating': 69,
    'user_rating': 57,
    'average_rating': 63
  },
  {
    'releaseDate': 1380006000000,
    'critic_rating': 79,
    'user_rating': 75,
    'average_rating': 77
  },
  {
    'releaseDate': 1321344000000,
    'critic_rating': 78,
    'user_rating': 79,
    'average_rating': 78.5
  },
];

const sortedAlbums = allAlbums.sort((a, b) => a.releaseDate - b.releaseDate);
console.log(sortedAlbums);

[
  {
    "releaseDate": 1321344000000,
    "critic_rating": 78,
    "user_rating": 79,
    "average_rating": 78.5
  },
  {
    "releaseDate": 1380006000000,
    "critic_rating": 79,
    "user_rating": 75,
    "average_rating": 77
  },
  {
    "releaseDate": 1461913200000,
    "critic_rating": 69,
    "user_rating": 57,
    "average_rating": 63
  }
]

//All albums is the result of asynchronous action so better store it
//  as a result of asynchronous action (promise)
var allAlbums = $.Deferred().resolve([]);
function Album(releaseDate) {
  this.releaseDate = new Date(releaseDate).getTime();
}
const logSorted = (message,albums) =>
  albums.then(
    albums => albums.map(x=>x).sort((a, b) => a.releaseDate - b.releaseDate)
  ).then(
    sortedAlbums=>console.log(message,sortedAlbums)
  );
$(function () {
  //set allAlbums to a promise
  allAlbums = $.ajax({
    url: 'https://api-marcalencc-metacritic-v1.p.mashape.com/person/drake/album',
    type: 'get',
    dataType: 'json',
    headers: {
      "X-Mashape-Key": "----------------------------",
      "Accept": "application/json"
    }
  })
  .then(
    data =>
      data[0].CreditMediaPairItems.map(
        val =>
          new Album(val.Item.ReleaseDate)
      )
  );
  allAlbums.then(
    albums=>
      logSorted(
        "all albums is set with results so should log sorted:",
        albums
      )
  );
});

//it is kind of pointless to try and use all albums outside of he document ready
//  because document ready is an event that you don't know when it happens unless
//  code is inside document ready.
logSorted("all albums should be empty so sorted is empty too",allAlbums);

const sorter = getter => comparer => (a,b) => 
  comparer(getter(a),getter(b));

const compareNumbers = (a,b)=>a-b;

const compareStrings = (a,b)=>a>b?1:(a<b)?-1:0;

const sortReleaseDate = sorter(x=>x.releaseDate)(compareNumbers);

const sortSomeStringValue = sorter(x=>x.someString)(compareStrings);

const sort = (sorters) => (a,b) => {
  const recur = (index) =>{
    if(index===sorters.length){
      return 0;
    }
    const [sorter,direction] = sorters[index];
    const result = sorter(a,b);
    if(result!==0){
      return result*direction;
    }
    return recur(index+1);
  }
  return recur(0);
};

//example on how to use:
const sampleArray = [
  {someString:"a",releaseDate:3},
  {someString:"a",releaseDate:2},
  {someString:"a",releaseDate:1},
  {someString:"b",releaseDate:3},
  {someString:"b",releaseDate:2},
  {someString:"b",releaseDate:1},
  {someString:"c",releaseDate:3},
  {someString:"c",releaseDate:2},
  {someString:"c",releaseDate:1}
];

console.log(
  "someString descending then releaseDate ascending",
  JSON.stringify(
    sampleArray
    .map(x=>x)//copy so we won't change original
    .sort(
      sort([
        [sortSomeStringValue,-1],//sort by by some string descending
        [sortReleaseDate,1]//sort by release date ascending
      ])
    ),
    undefined,
    2
  )
);

console.log(
  "releaseDate descending then some string ascending",
  JSON.stringify(
    sampleArray
    .map(x=>x)//copy so we won't change original
    .sort(
      sort([
        [sortReleaseDate,-1],//sort by release date descending
        [sortSomeStringValue,1]//sort by by some string ascending
      ])
    ),
    undefined,
    2
  )
)

console.log(
  "only releaseDate descending",
  JSON.stringify(
    sampleArray
    .map(x=>x)//copy so we won't change original
    .sort(
      sort([
        [sortReleaseDate,-1]//sort by release date descending
      ])
    ),
    undefined,
    2
  )
)