syntax error, unexpected '!' in laravel 5.1

I am trying to use Html:: class in blade template 5.1, I have tried everything before I was getting error of class HTML not found but when I use {{ !! HTML:: !!}} before html, the error is now FatalErrorException in 75e2b4fe5a49ad69bec8641db04b4b16 line 10: syntax error, unexpected '!' guide me please here is code, Index.blade.php

    <li> {{ !! Html:: link_to_route('author',
    $authorname->name, array($authorname->id)) !! }}</li>

    Route: Route::get('authors/{id}', array('as' => 'author', 'uses' => 
    'authors_controller@get_view'));

    Composer.json: `"require": {
    "laravelcollective/html": "5.1.*"
   },

   app.php Providers: `Collective\Html\HtmlServiceProvider::class,`             
   app.php Aliases: 
   'Form' => Collective\Html\FormFacade::class,
   'Html' => Collective\Html\HtmlFacade::class,

and I have used the composer update command or composer require illuminate/html all of these things

via Chebli Mohamed