Return a Value from a Function with Return in JavaScript

In JavaScript, a function can return a value using the return keyword. When a return statement is executed, the function stops executing and the value of the return statement is returned to the calling code. For example:

function add(a, b) {
  return a + b;
}

let result = add(2, 3); // result is set to 5

In this example, the function add() takes in two parameters, a and b, and returns their sum. The calling code assigns the returned value of the function to the variable result.

It’s also possible to not return any value in a function, in this case the function return undefined by default.

function noReturn() {
  console.log("Hello World");
}

console.log(noReturn()); // "Hello World" and undefined

It’s important to note that once a return statement is executed, the function stops executing and no further code within the function will be executed.

Here are a few more details about using the return keyword in JavaScript:

• A function can have multiple return statements, but execution will only reach one of them depending on the flow of the code. For example, if a function has multiple if-else statements and each branch has a different return statement, only the return statement in the branch that gets executed will be returned.
• The return keyword can be used to return any type of data, including numbers, strings, booleans, objects, and arrays.
• Functions can also return other functions, or even return themselves (recursive functions).
• When a function is called and its return value is not used or assigned to a variable, the returned value is effectively discarded. For example, in the following code, the returned value of the add() function is not used, so it doesn’t affect the output:

function add(a, b) {
  return a + b;
}

console.log("The result is not used");
add(2, 3);

• A function can return a promise, which can be used to handle asynchronous operations.
• A return statement with no value, or with no expression after the return keyword, will return undefined.