all files / modules/ AsyncUtils.js

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
1×
295×
 
1×
295×
295×
 
 
1×
493×
 
 
493×
431×
 
62×
 
 
 
295×
 
 
1×
86×
86×
 
86×
 
 
86×
 
1×
168×
 
 
168×
 
 
 
168×
 
168×
 
168×
86×
 
 
 
86×
168×
168×
 
 
 
 
 
export function loopAsync(turns, work, callback) {
  let currentTurn = 0, isDone = false
 
  function done() {
    isDone = true
    callback.apply(this, arguments)
  }
 
  function next() {
    Iif (isDone)
      return
 
    if (currentTurn < turns) {
      work.call(this, currentTurn++, next, done)
    } else {
      done.apply(this, arguments)
    }
  }
 
  next()
}
 
export function mapAsync(array, work, callback) {
  const length = array.length
  const values = []
 
  Iif (length === 0)
    return callback(null, values)
 
  let isDone = false, doneCount = 0
 
  function done(index, error, value) {
    Iif (isDone)
      return
 
    Iif (error) {
      isDone = true
      callback(error)
    } else {
      values[index] = value
 
      isDone = (++doneCount === length)
 
      if (isDone)
        callback(null, values)
    }
  }
 
  array.forEach(function (item, index) {
    work(item, index, function (error, value) {
      done(index, error, value)
    })
  })
}