From add7435757b95f4c4eb883814cb40cdf79d6614d Mon Sep 17 00:00:00 2001 From: Angelos Chalaris Date: Wed, 13 Dec 2017 14:18:52 +0200 Subject: [PATCH] Build README --- README.md | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/README.md b/README.md index 3ca38fa97..9b81f83ee 100644 --- a/README.md +++ b/README.md @@ -464,20 +464,20 @@ const powerset = arr => ### Promisify -Creates a promisified version of the given callback-style function. In Node 8+, you -can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original) +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)* ```js const promisify = func => (...args) => new Promise((resolve, reject) => func(...args, (err, result) => - err - ? reject(err) - : resolve(result)) - ) -// const stat = promisify(fs.stat) -// stat('foo.txt') -> Promise resolves if `foo.txt` exists, otherwise rejects + err ? reject(err) : resolve(result)) + ); +// const delay = promisify((d, cb) => setTimeout(cb, d)) +// delay(2000).then(() => console.log('Hi!')) -> Promise resolves after 2s ``` ### Random integer in range