Conditional expressions
The result of a conditional expression can be one value or another, depending on a condition.
gross revenue = $10k tax = if gross revenue > $5k then 10% else 5% net income = gross revenue - tax
A conditional expression can also appear as an operand; in this case, it should be placed in parentheses.
gross revenue = $10k net income = gross revenue - (if gross revenue > $5k then 10% else 5%)