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# p-locate [![Build Status](https://travis-ci.com/sindresorhus/p-locate.svg?branch=master)](https://travis-ci.com/github/sindresorhus/p-locate)
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> 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
```
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$ npm install p-locate
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```
## 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',
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'rainbow.png', // Only this one actually exists on disk
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'pony.png'
];
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(async () => {
const foundPath = await pLocate(files, file => pathExists(file));
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console.log(foundPath);
//=> 'rainbow'
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})();
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```
*The above is just an example. Use [`locate-path` ](https://github.com/sindresorhus/locate-path ) if you need this.*
## API
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### pLocate(input, tester, options?)
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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
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Type: `Iterable<Promise | unknown>`
An iterable of promises/values to test.
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#### tester(element)
Type: `Function`
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This function will receive resolved values from `input` and is expected to return a `Promise<boolean>` or `boolean` .
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#### options
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Type: `object`
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##### concurrency
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Type: `number` \
Default: `Infinity` \
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Minimum: `1`
Number of concurrently pending promises returned by `tester` .
##### preserveOrder
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Type: `boolean` \
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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 )
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