Gave names to anonymous functions. Tried to be as semantic as possible.

docs/api-routes/dynamic-api-routes.md

@@ -16,7 +16,7 @@ API routes support [dynamic routes](/docs/routing/dynamic-routes.md), and follow
 For example, the API route `pages/api/post/[pid].js` has the following code:
 
 ```js
-export default (req, res) => {
+export default function PostId(req, res){
   const {
     query: { pid },
   } = req
@@ -68,7 +68,7 @@ And in the case of `/api/post/a/b`, and any other matching path, new parameters
 An API route for `pages/api/post/[...slug].js` could look like this:
 
 ```js
-export default (req, res) => {
+export default function CatchSlug(req, res){
   const {
     query: { slug },
   } = req

docs/api-routes/introduction.md

@@ -22,7 +22,7 @@ Any file inside the folder `pages/api` is mapped to `/api/*` and will be treated
 For example, the following API route `pages/api/user.js` handles a `json` response:
 
 ```js
-export default (req, res) => {
+export default function UserName(req, res){
   res.statusCode = 200
   res.setHeader('Content-Type', 'application/json')
   res.end(JSON.stringify({ name: 'John Doe' }))
@@ -37,7 +37,7 @@ For an API route to work, you need to export as default a function (a.k.a **requ
 To handle different HTTP methods in an API route, you can use `req.method` in your request handler, like so:
 
 ```js
-export default (req, res) => {
+export default function PostReq(req, res){
   if (req.method === 'POST') {
     // Process a POST request
   } else {

docs/api-routes/response-helpers.md

@@ -15,7 +15,7 @@ description: API Routes include a set of Express.js-like methods for the respons
 The response (`res`) includes a set of Express.js-like methods to improve the developer experience and increase the speed of creating new API endpoints, take a look at the following example:
 
 ```js
-export default (req, res) => {
+export default function ResHelper(req, res){
   res.status(200).json({ name: 'Next.js' })
 }
 ```