export_default.md

Export Default

Challenge Description

In the export lesson, you learned about the syntax referred to as a named export. This allowed you to make multiple functions and variables available for use in other files.

There is another export syntax you need to know, known as export default. Usually you will use this syntax if only one value is being exported from a file. It is also used to create a fallback value for a file or module.

Here is a quick example of export default:

export default const add = (x,y) => { return x + y; }

>There is a one major feature of `export default` you must never forget-since it is used to declare a fallback value for a module or file, **you can only have one value be a default export in each module or file**. 

### Instructions
>The following function should be the fallback value for the module. Please add the necessary code to do so.

### Challenge Seed
```javascript
const subtract = (x,y) => {return x - y;}

Challenge Tests

assert(code.match(/export\s+default\s+const\s+subtract\s+=\s+\(x,y\)\s+=>\s+{return\s+x\s-\s+y;}/ig))

Challenge Solution

export default const subtract = (x,y) => {return x - y;}