public function detachLeft() : void
    {
        if ($this->left) {
            $this->left->setParent(null);

            $this->left = null;
        }
    }
public function detachLeft() : void
    {
        if ($this->left) {
            $this->left->setParent(null);

            $this->left = null;
        }
    }
public function detachLeft ( ) : void { if ( $ this -> left ) { $ this -> left -> setParent ( null ) ; $ this -> left = null ; } }
Detach the left child node.
Detach the left child node .