Frequent question: Is return mandatory in JavaScript?

Is return necessary in JavaScript function?

A function returns undefined by default. The use of return is therefore only necessary if you want to override the default behaviour. The Javascript community seem to dislike unnecessary verbose code. It might even be said to be a sport to make the code as short and compact as possible.

Why is return important in JavaScript?

When a return statement is used in a function body, the execution of the function is stopped. If specified, a given value is returned to the function caller. For example, the following function returns the square of its argument, x , where x is a number. If the value is omitted, undefined is returned instead.

Does a function have to have a return?

Answer. NO, a function does not always have to have an explicit return statement. If the function doesn’t need to provide any results to the calling point, then the return is not needed.

Why do we return in function?

A return statement ends the execution of a function, and returns control to the calling function. Execution resumes in the calling function at the point immediately following the call. A return statement can return a value to the calling function. For more information, see Return type.

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What is the difference between return and console log?

return is a statement that allows a function to output a value back to where it was called. console. log is a function that lets us inspect values for debugging purposes.

Is return the same as return true?

No. They are not the same. Returning false from a function returns the boolean false , where a void return will return undefined .

What are the functions of JavaScript?

JavaScript provides functions similar to most of the scripting and programming languages. In JavaScript, a function allows you to define a block of code, give it a name and then execute it as many times as you want. A JavaScript function can be defined using function keyword.

What does return true do in JavaScript?

Rule #1. Every function in JavaScript returns undefined unless otherwise specified. As expected, when we invoke our function undefined is returned in the console. As you can see, our explicitly returned true value replaces the default undefined value.

Does every function return a value?

So to recap: No, a JS function needn’t return anything as far as your code goes. But as far as the JS engines are concerned: a function always returns something, be it explicitly via a return statement, or implicitly. If a function returns implicitly, its return value will always be undefined.

Does every function need a return statement?

Regardless of how long and complex your functions are, any function without an explicit return statement, or one with a return statement without a return value, will return None .

What will be returned if f AB is called?

If a and b both are equal, then this function will return 0. In other case function f(a,b) will return positive integer and upon calling function g it will always return 1.

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What is called the functions with no return value?

Correct Option: A

Void functions does not return a value. Functions with no return value are sometimes called procedures.

Why return is used in Python?

The Python return keyword exits a function and instructs Python to continue executing the main program. The return keyword can send a value back to the main program. A value could be a string, a tuple, or any other object. … This is useful because it allows us to process data within a function.