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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