Laravel 5 - ORM has() Relationship (Inverse - notHas)

In the Laravel 5 I can find all posts that have at least one comment using has method:

// Retrieve all posts that have at least one comment...
$posts = App\Post::has('comments')->get();

As theres no method like notHas, how can I find all posts that have no comments? (remembering that it's a hasMany relationship)

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Reference:

Querying Relationship Existence

http://ift.tt/1IbMHFY

via Chebli Mohamed