I encounter a error: 

```
Some mandatory parameters are missing ("users") to generate a URL for route "users.update".

```

I have this set on my view: 

```
{{ Form::open( array('action' => array('UsersController@update')) )  }}

         <div>  {{ Form::label('username', 'Username:') }}
            {{ Form::text('username', $user->username , array('class' => 'form-control')) }}</div> 

             <div>  {{ Form::label('email', 'Email Address:') }}
            {{ Form::text('email', $user->email , array('class' => 'form-control')) }}</div> 

            <div>  {{ Form::label('new_password', 'New Password:') }}
            {{ Form::text('new_password', '', array('class' => 'form-control')) }} </div> 

             <div>  {{ Form::label('old_password', 'Old Password:') }}
            {{ Form::text('password', '', array('class' => 'form-control')) }} </div>

            {{ Form::submit() }}

{{ Form::close() }}

```

I also have a function in my controller linked to update:

```
public function update() {
        return 'This is an update';
    }

```

And finally, when I check all the routes available in Artisan command, I found that the update has a route to: `users/{users}`

What's wrong with my codes? I'm trying to update a user and it throws this error.