Code as javaScript function parameters?

Question

JavaScript

Hello.
I foresee the answer that I searched badly in Google.
But at least I tried :)

I want to write a function that will take 2 parameters:
1. variable(s)
2. Javascript code.

So that for example I could call my function like this:
fun1("Hi", function(data) {
here any number of lines of JavaScript code
and would be executed only after the work is completed or the result of
the fun1 function has arrived
});

I'll never know how to do it ...
Tell me or point your finger at the theory so that it's clear :)
thanks in advance!

Answer 1

That is, it is necessary that the function be called only after the parent function has been executed? Well, it's unlikely.
Could be something like this:

(function(data) {
  dosomething();
})(data = fun1("Привет"));

Answer 2

You asked yourself, you answered...

function fun1(d, f){
   //code
  f(d);
}

fun1("Привет", function(data){
  alert(data);
});

Answer 3

To the above, I will add that google "javascript callback function".