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Moving semicolon, changing example in promisify.md

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Daniel Ramos
2017-12-13 12:15:39 +00:00
parent 1a0d41d2b8
commit babb858ce2
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snippets/promisify.md
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@ -1,15 +1,14 @@
### Promisify ### Promisify
Creates a promisified version of the given callback-style function. In Node 8+, you Use currying to return a function returning a Promise that calls the original function. Use the rest operator to pass in all the parameters. In Node 8+, you can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original)
can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original)
```js ```js
const promisify = func => const promisify = func =>
(...args) => (...args) =>
new Promise((resolve, reject) => new Promise((resolve, reject) =>
func(...args, (err, result) => func(...args, (err, result) =>
err ? reject(err) : resolve(result)); err ? reject(err) : resolve(result))
) );
// const stat = promisify(fs.stat) // const delay = promisify((d, cb) => setTimeout(cb, d))
// stat('foo.txt') -> Promise resolves if `foo.txt` exists, otherwise rejects // delay(2000).then(() => console.log('Hi!')) -> Promise resolves after 2s
``` ```