# 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 ``` $ 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` #### tester(element) Type: `Function` Expected to return a `Promise` 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) ## License MIT © [Sindre Sorhus](https://sindresorhus.com)