public function testKeyWithLambda() {
		$key = function() {
			return 'lambda_key';
		};

		$result = Cache::key($key);
		$expected = 'lambda_key';
		$this->assertIdentical($expected, $result);

		$key = function() {
			return 'lambda key';
		};

		$result = Cache::key($key);
		$expected = 'lambda key';
		$this->assertIdentical($expected, $result);

		$key = function($data = array()) {
			$defaults = array('foo' => 'foo', 'bar' => 'bar');
			$data += $defaults;
			return 'composed_key_with_' . $data['foo'] . '_' . $data['bar'];
		};

		$result = Cache::key($key, array('foo' => 'boo', 'bar' => 'far'));
		$expected = 'composed_key_with_boo_far';
		$this->assertIdentical($expected, $result);
	}