Can a function return a function JavaScript?
Functions are the same data as numbers or strings, so functions can be passed to other functions as arguments, as well as returned from functions. We can even define a function inside another function and return it outside. … Always, when you see such calls f()()() , know: the functions are back !
Can you return in JavaScript?
The return operator is used to return a value from inside a function. … You can return any valid JavaScript object: strings, booleans, objects, arrays, and even other functions.
What is it called when a function returns a function?
In mathematics and computer science, a higher-order function is a function that does at least one of the following: takes one or more functions as arguments (i.e. procedural parameters), returns a function as its result.
Do you always have to return something from a function?
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 need return 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.
What is return true in JavaScript?
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.
What is return in a function?
A return is a value that a function returns to the calling script or function when it completes its task. A return value can be any one of the four variable types: handle, integer, object, or string. The type of value your function returns depends largely on the task it performs.
What does it mean to return a 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.
When must a function return by value?
If a function is defined as having a return type of void , it should not return a value. In C++, a function which is defined as having a return type of void , or is a constructor or destructor, must not return a value. If a function is defined as having a return type other than void , it should return a value.
Do you always have to return something from a function JavaScript?
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.
What should a function return?
When should a function return what?
- A function should return the value you want to return to the caller. …
- A function to return the absolute difference of two values should not be called min . …
- Note that, in modern C, int min(x, y) is not a proper declaration.
Should a function always return a value JavaScript?
4 Answers. All JavaScript functions return something. If an explicit return is omitted, undefined is returned automatically instead. … To my knowledge, unless you need it to return something, a function doesn’t have to return anything.