src/TokenList.php
public function toggle(string $token):bool {
		if($this->contains($token)) {
			$this->remove($token);

			return false;
		}

		$this->add($token);

		return true;
	}
public function toggle(string $token):bool {
		if($this->contains($token)) {
			$this->remove($token);

			return false;
		}

		$this->add($token);

		return true;
	}
Removes $token from the underlying attribute value and returns false. If
$token doesn't exist, it's added and the function returns true.
@param string $token
@return bool true if token is added, false if token is removed.