JavaScript Ternary Operator
JavaScript’s ability to handle multiple conditions enables your program to run distinct code blocks according to whether or not specific expressions evaluate to true. Often called the ternary operator, the conditional operator is one of the tools available for this. Being the only operator in JavaScript that needs three operands, it is noteworthy.
The ternary operator is expressed as follows: condition? operand2: operand3. The evaluation and interpretation of an expression as a boolean value constitutes the first operand (condition). Operand2, also known as thenExpression, is the second operand that is evaluated and its value is returned if the condition evaluates to a truthy value. Operand3 or elseExpression, the third operand, is evaluated and its value is returned if the condition evaluates to a false value. It’s important to note that the second and third operands are skipped and just one is evaluated. Short-circuit evaluation is the name given to this characteristic.
Conceptually, the colon (:) can be viewed as “else” and the question mark (?) as “then”. The following structure should be remembered: “if operand1, then operand2, else operand3”.
Many people refer to the ternary operator as a shortcut for creating an if else statement, especially when the objective is to execute a brief operation or conditionally assign a value to a variable.
Similar to allocating an access level according to age, the following example illustrates its application for conditional assignment:
let age = 20; // Declare and initialise a variable ‘age’
let access; // Declare a variable ‘access’; its value is initially undefined
// Use the ternary operator to assign a value to ‘access’ based on a condition
// Condition: age < 18 (Is age less than 18?)
// If true, assign “denied”. If false, assign “allowed”.
access = age < 18 ? “denied” : “allowed”;
// Output the value of ‘access’ to the console
console.log(access); // Expected output: “allowed”
// Reassign a new value to the ‘age’ variable
age = 16;
// Re-evaluate the condition using the new ‘age’ value and assign the result to ‘access’
access = age < 18 ? “denied” : “allowed”;
// Output the new value of ‘access’ to the console
console.log(access); // Expected output: “denied”
This is equivalent to the following if else statement:
let age = 20;
let access;
if (age < 18) {
access = “denied”;
} else {
access = “allowed”;
}
console.log(access);
For very short actions, you can also specify an action directly in the ternary statement:
let age = 16;
age < 18 ? console.log(“Access denied.”) : console.log(“Access allowed.”); //
Your code can occasionally fit on a single line thanks to the ternary operator. If else statements are useful for resolving assignment values, smaller expressions, and function return values.
The ternary operator is simple, but complex conditions or expressions that span numerous lines can make code harder to read. For very brief actions or straightforward conditional assignments, it is typically advised. If there are several comparison arguments in the logic, a standard if-else structure is required. Multiple statements within its branches cannot be supported by the ternary operator without the usage of the comma operator, and control flow statements such as break and continue are not supported.
The main goals of the ternary operator (? 🙂 and the if statement should be noted while comparing them. An expression-based variant of the if statement, the ternary operator is intended to return one of two values. Alternatively, the if statement is a control statement that can be used to run several code branches. When executing separate code blocks, if statements are frequently easier to follow than ternary operators.
Similar to the nullish coalescing operator (??), which is immediately below the logical OR (||) operator, and only marginally higher than assignment (=), the ternary operator has a comparatively low precedence. Use brackets around conditions and phrases to increase readability. You need explicit brackets to use the ternary operator with the logical AND (&&) or OR (||) operators.
The JavaScript ternary operator (condition? expr1 : expr2) makes basic conditional selections and assignments strong and concise. Its readability declines with complexity, making if else structures better suitable for more complex branching, even though they are helpful for brief, straightforward conditional logic.