public boolean subsEquals(Operator other) {
		if (this == other)
			return true;
		if (other.subExpressions == null)
			return (subExpressions == null);

		if (subExpressions.length != other.subExpressions.length)
			return false;

		for (int i = 0; i < subExpressions.length; i++) {
			if (!subExpressions[i].equals(other.subExpressions[i]))
				return false;
		}
		return true;
	}