Just wanted to point out that OR combines two conditions. As far as I know; it means that 'Expression A' and 'Expression B' are evaluated and then the OR operator is applied for evaluating the final result of the 'Expression A OR B'.
So,
IF A OR B
BEGIN
{do something}
END
is not the same as
IF A
BEGIN
{do something}
END
IF B
BEGIN
{do something}
END