The JavaScript question mark operator, also known as the ternary conditional operator, is a concise and versatile tool used to evaluate expressions and conditionally assign values based on their truthiness. It takes the following syntax: condition ? true_value : false_value
where condition
is any expression that evaluates to a boolean value (true or false), true_value
is the value to be assigned if the condition is true, and false_value
is the value to be assigned if the condition is false.
The question mark operator is particularly useful for simplifying conditional statements and making code more readable and maintainable. For instance, consider the following traditional if-else statement: if (user.age >= 18) {status = 'adult';} else {status = 'minor';}
Using the question mark operator, we can rewrite this statement more concisely as: const status = user.age >= 18 ? 'adult' : 'minor';
This compact syntax improves code readability and reduces the potential for errors.