protected function handleMixins(Node $node)
    {

        $mixins = $node->findArray('mixin');

        //Save all mixins in $this->mixins for our mixinCalls to reference them
        foreach ($mixins as $mixinNode) {

            if (isset($this->mixins[$mixinNode->name]) && !$this->options['replace_mixins'])
                $this->throwException(
                    "A mixin with the name [$mixinNode->name] is already defined. Rename the it or enable the".
                    "[`replace_mixins`]-option to be able to overwrite it",
                    $mixinNode
                );
            else if (isset($this->mixins[$mixinNode->name]))
                $this->mixins[$mixinNode->name]->parent->remove($this->mixins[$mixinNode->name]);

            $this->mixins[$mixinNode->name] = $mixinNode;
        }

        //Handle the mixins
        foreach ($this->mixins as $mixinNode)
            $this->handleMixin($mixinNode);

        return $this;
    }