protected function isAttributeMatching(array $criterion)
	{
		if ( !isset($criterion[self::CRITERION_ATTRS]) ) {
			return true;
		}

		foreach ( $criterion[self::CRITERION_ATTRS] as $attribute => $definition ) {
			if ( $this->isValueMatchingCriterionDefinition($this->getAttribute($attribute), $definition) ) {
				return true;
			}
		}

		return false;
	}