JavaScript ternary operator example with functions

The JavaScript ternary operator is a shorthand for the if-else statement. It evaluates a condition and returns one of two values based on whether the condition is true or false. The syntax of the ternary operator is:

condition ? valueIfTrue : valueIfFalse

Example of Using the Ternary Operator with Functions

Below is an example where we use the ternary operator to conditionally return different results based on a function’s input.

Example: Checking Age for Voting Eligibility

Let’s write a function that checks if a person is eligible to vote. We’ll use the ternary operator to decide the message based on the age.

function checkEligibility(age) {
  return age >= 18 ? "You are eligible to vote!" : "Sorry, you are not eligible to vote.";
}

console.log(checkEligibility(20)); // Output: "You are eligible to vote!"
console.log(checkEligibility(16)); // Output: "Sorry, you are not eligible to vote."

Explanation:

• The function checkEligibility(age) takes an age as an argument.
• The ternary operator checks if the age is greater than or equal to 18.
  • If the condition is true (age >= 18), it returns "You are eligible to vote!".
  • If the condition is false, it returns "Sorry, you are not eligible to vote.".

Another Example: Greeting a User Based on Time of Day

Let’s create a function that greets the user depending on the time of day (morning, afternoon, or evening).

function greetUser(hour) {
  return hour < 12
    ? "Good Morning!"
    : hour < 18
    ? "Good Afternoon!"
    : "Good Evening!";
}

console.log(greetUser(9));  // Output: "Good Morning!"
console.log(greetUser(14)); // Output: "Good Afternoon!"
console.log(greetUser(20)); // Output: "Good Evening!"

Explanation:

• The function greetUser(hour) uses nested ternary operators.
• The first condition checks if the hour is less than 12 (morning).
• If it’s not, the second condition checks if the hour is less than 18 (afternoon).
• If neither condition is true, it assumes it’s evening.

Benefits of Using the Ternary Operator

• Conciseness: The ternary operator provides a compact way to write simple conditional logic.
• Readability: It is easier to read for short conditions compared to writing multiple if-else statements.

However, for more complex conditions or when you need multiple statements in each branch, traditional if-else blocks might be clearer.

Let me know if you’d like more examples or clarifications!