blob: 68b96a47ef294578d73132ae1c4e4b8c143526e5 (
plain)
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
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
# p-locate [](https://travis-ci.org/sindresorhus/p-locate)
> Get the first fulfilled promise that satisfies the provided testing function
Think of it like an async version of [`Array#find`](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/find).
## Install
```
$ npm install --save p-locate
```
## Usage
Here we find the first file that exists on disk, in array order.
```js
const pathExists = require('path-exists');
const pLocate = require('p-locate');
const files = [
'unicorn.png',
'rainbow.png', // only this one actually exists on disk
'pony.png'
];
pLocate(files, file => pathExists(file)).then(foundPath => {
console.log(foundPath);
//=> 'rainbow'
});
```
*The above is just an example. Use [`locate-path`](https://github.com/sindresorhus/locate-path) if you need this.*
## API
### pLocate(input, tester, [options])
Returns a `Promise` that is fulfilled when `tester` resolves to `true` or the iterable is done, or rejects if any of the promises reject. The fulfilled value is the current iterable value or `undefined` if `tester` never resolved to `true`.
#### input
Type: `Iterable<Promise|any>`
#### tester(element)
Type: `Function`
Expected to return a `Promise<boolean>` or boolean.
#### options
Type: `Object`
##### concurrency
Type: `number`<br>
Default: `Infinity`<br>
Minimum: `1`
Number of concurrently pending promises returned by `tester`.
##### preserveOrder
Type: `boolean`<br>
Default: `true`
Preserve `input` order when searching.
Disable this to improve performance if you don't care about the order.
## Related
- [p-map](https://github.com/sindresorhus/p-map) - Map over promises concurrently
- [p-filter](https://github.com/sindresorhus/p-filter) - Filter promises concurrently
- [p-any](https://github.com/sindresorhus/p-any) - Wait for any promise to be fulfilled
- [More…](https://github.com/sindresorhus/promise-fun)
## License
MIT © [Sindre Sorhus](https://sindresorhus.com)
|
