presto-matching/src/main/java/io/prestosql/matching/Captures.java/Captures/hashCode
class Captures:    @Override
    public int hashCode()
    {
        int result = capture != null ? capture.hashCode() : 0;
        result = 31 * result + (value != null ? value.hashCode() : 0);
        result = 31 * result + (tail != null ? tail.hashCode() : 0);
        return result;
    }