Once a return operator is executed, anything after it inside a function doesn’t run. I often use the return operator to bail if certain conditions aren’t met. For example, if a function required an element to exist, you could use return to stop it from running if the element isn’t in the DOM.
Why do we use return in JavaScript?
The return statement is used to return a particular value from the function to the function caller. … The return statement should be the last statement in a function because the code after the return statement will be unreachable. We can return primitive values (such as Boolean, number, string, etc.)
What is the purpose of return?
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.
What is return keyword in JavaScript?
The return keyword in JavaScript is a keyword to build a statement that ends JavaScript code execution. … JavaScript will then give back control to the caller and continue code execution from there: function fnExample() { return; console. log(“Hi from function”); } fnExample(); // nothing will be printed console.
Should JavaScript functions always return?
4 Answers. All JavaScript functions return something. If an explicit return is omitted, undefined is returned automatically instead. When a function returns, its instance is wiped out from memory, which also frees all the variables in its scope to be wiped out if nothing else points to them.
How does return in JavaScript work?
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.
How do you return a value from a function?
To return a value from a function, you must include a return statement, followed by the value to be returned, before the function’s end statement. If you do not include a return statement or if you do not specify a value after the keyword return, the value returned by the function is unpredictable.
How do I use return?
A return statement is used to end the execution of the function call and “returns” the result (value of the expression following the return keyword) to the caller. The statements after the return statements are not executed. If the return statement is without any expression, then the special value None is returned.
What does return mean programming?
In programming, return is a statement that instructs a program to leave the subroutine and go back to the return address. … In most programming languages, the return statement is either return or return value, where value is a variable or other information coming back from the subroutine.
Does return break while loop Python?
Using a return inside of a loop will break it and exit the function even if the iteration is still not finished.
What does JavaScript do?
Here are some basic things JavaScript is used for:
- Adding interactive behavior to web pages. JavaScript allows users to interact with web pages. …
- Creating web and mobile apps. …
- Building web servers and developing server applications. …
- Game development.
Who defines JavaScript?
JavaScript is a programming language commonly used in web development. It was originally developed by Netscape as a means to add dynamic and interactive elements to websites.
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.