You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
94 lines
2.5 KiB
94 lines
2.5 KiB
1 month ago
|
# p-locate [![Build Status](https://travis-ci.com/sindresorhus/p-locate.svg?branch=master)](https://travis-ci.com/github/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 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'
|
||
|
];
|
||
|
|
||
|
(async () => {
|
||
|
const foundPath = await pLocate(files, file => pathExists(file));
|
||
|
|
||
|
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 | unknown>`
|
||
|
|
||
|
An iterable of promises/values to test.
|
||
|
|
||
|
#### tester(element)
|
||
|
|
||
|
Type: `Function`
|
||
|
|
||
|
This function will receive resolved values from `input` and is expected to return a `Promise<boolean>` or `boolean`.
|
||
|
|
||
|
#### options
|
||
|
|
||
|
Type: `object`
|
||
|
|
||
|
##### concurrency
|
||
|
|
||
|
Type: `number`\
|
||
|
Default: `Infinity`\
|
||
|
Minimum: `1`
|
||
|
|
||
|
Number of concurrently pending promises returned by `tester`.
|
||
|
|
||
|
##### preserveOrder
|
||
|
|
||
|
Type: `boolean`\
|
||
|
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)
|
||
|
|
||
|
---
|
||
|
|
||
|
<div align="center">
|
||
|
<b>
|
||
|
<a href="https://tidelift.com/subscription/pkg/npm-p-locate?utm_source=npm-p-locate&utm_medium=referral&utm_campaign=readme">Get professional support for this package with a Tidelift subscription</a>
|
||
|
</b>
|
||
|
<br>
|
||
|
<sub>
|
||
|
Tidelift helps make open source sustainable for maintainers while giving companies<br>assurances about security, maintenance, and licensing for their dependencies.
|
||
|
</sub>
|
||
|
</div>
|