reactphp/react — pull request #203 by jsor (2013-06-07 19:37:47+00:00)
Title: [Http] Extend Response

Use case could be for example a session middleware:

```php
function ($request, $response) {
// Read session cookie from $request, create session, etc...

$response->on('header', function() use ($response) {
$reponse->setHeader('Set-Cookie', '...sessioncookie...');
});
};
```