### nthArg

Creates a function that gets the argument at index `n`. If `n` is negative, the nth argument from the end is returned.

Use `Array.slice()` to get the desired argument at index `n`.

```js
const nthArg = n => (...args) => args.slice(n)[0];
```

```js
const third = nthArg(2);
third(1,2,3); // 3
third(1,2); // undefined
const last = nthArg(-1);
last(1,2,3,4,5); // 5
```