Sorting an array of objects by 'desc' with numbers first

Question

I'm trying to sort an array of objects by descending and beginning with number first, here's what I'm having:

var users = [
  { 'user': 'fred',   'a': 48 },
  { 'user': 'barney', 'a': 'b' },
  { 'user': 'fred',   'a': 40 },
  { 'user': 'barney', 'a': 'c' }
];
_.orderBy(users, 'a', 'desc');

result:

0: Object {a: "b", user: "barney"}
1: Object {a: "c", user: "barney"}
2: Object {a: 48, user: "fred"}
3: Object {a: 40, user: "fred"}

expected result:

0: Object {a: 48, user: "fred"}
1: Object {a: 40, user: "fred"}
2: Object {a: "b", user: "barney"}
3: Object {a: "c", user: "barney"}

Answer 1

You can provide multiple sort keys ("iteratees") and the order for each key

_.orderBy(users, [x => isNaN(x.a), 'a'], ['asc', 'desc']);

This will, however, sort the strings descending as well (that is, the result will be 48, 40, c, b.

var users = [
  { 'user': 'x',   'a': 'a' },
  { 'user': 'x',   'a': 948 },
  { 'user': 'x',   'a': 48 },
  { 'user': 'x',   'a': -480 },
  { 'user': 'x',   'a': 'c' },
  { 'user': 'x',   'a': 548 },
  { 'user': 'x',   'a': 4558 },
  { 'user': 'x',   'a': 148 },
  { 'user': 'x',   'a': 4834534 },
  { 'user': 'x',   'a': 1 },
  { 'user': 'x',   'a': 'b' },
];

users = _.orderBy(users, [x => isNaN(x.a), 'a'], ['asc', 'desc']);
console.log(users)

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