Benefits of using the conditional ?: (ternary) operator

Question

What are the benefits and drawbacks of the ?: operator as opposed to the standard if-else statement. The obvious ones being:

Conditional ?: Operator

Answer 1

I find it particularly helpful when doing web development if I want to set a variable to a value sent in the request if it is defined or to some default value if it is not.

Answer 2

The advantage of the conditional operator is that it is an operator. In other words, it returns a value. Since if is a statement, it cannot return a value.

Answer 3

One thing to recognize when using the ternary operator that it is an expression not a statement.

In functional languages like scheme the distinction doesn't exists:

(if (> a b) a b)

Conditional ?: Operator "Doesn't seem to be as flexible as the if/else construct"

In functional languages it is.

When programming in imperative languages I apply the ternary operator in situations where I typically would use expressions (assignment, conditional statements, etc).

Answer 4

I'd recommend limiting the use of the ternary(?:) operator to simple single line assignment if/else logic. Something resembling this pattern:

if(<boolCondition>) {
    <variable> = <value>;
}
else {
    <variable> = <anotherValue>;
}

Could be easily converted to:

<variable> = <boolCondition> ? <value> : <anotherValue>;

I would avoid using the ternary operator in situations that require if/else if/else, nested if/else, or if/else branch logic that results in the evaluation of multiple lines. Applying the ternary operator in these situations would likely result in unreadable, confusing, and unmanageable code. Hope this helps.

Answer 5

The scenario I most find myself using it is for defaulting values and especially in returns

return someIndex < maxIndex ? someIndex : maxIndex;

Those are really the only places I find it nice, but for them I do.

Though if you're looking for a boolean this might sometimes look like an appropriate thing to do:

bool hey = whatever < whatever_else ? true : false;

Because it's so easy to read and understand, but that idea should always be tossed for the more obvious:

bool hey = (whatever < whatever_else);

Answer 6

I would basically recommend using it only when the resulting statement is extremely short and represents a significant increase in conciseness over the if/else equivalent without sacrificing readability.

Good example:

int result = Check() ? 1 : 0;

Bad example:

int result = FirstCheck() ? 1 : SecondCheck() ? 1 : ThirdCheck() ? 1 : 0;