Files
30-seconds-of-code/snippets/rearg.md
Angelos Chalaris fd35820293 Add rearg
2018-01-28 15:04:21 +02:00

26 lines
643 B
Markdown

### rearg
Creates a function that invokes the provided function with its arguments arranged according to the specified indexes.
Use `Array.reduce()` and `Array.indexOf()` to reorder arguments based on `indexes` in combination with the spread operator (`...`) to pass the transformed arguments to `fn`.
```js
const rearg = (fn, indexes) => (...args) =>
fn(
...args.reduce(
(acc, val, i) => ((acc[indexes.indexOf(i)] = val), acc),
Array.from({ length: indexes.length })
)
);
```
```js
var rearged = rearg(
function(a, b, c) {
return [a, b, c];
},
[2, 0, 1]
);
rearged('b', 'c', 'a'); // ['a', 'b', 'c']
```