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# p-locate [![Build Status](https://travis-ci.org/sindresorhus/p-locate.svg?branch=master)](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
```
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$ npm install --save 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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pLocate(files, file => pathExists(file)).then(foundPath => {
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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
### 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
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Type: `Iterable<Promise|any>`
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#### tester(element)
Type: `Function`
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Expected to return a `Promise<boolean>` or boolean.
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#### 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 )