Javascript: Can someone explain how these parameters are correct?

I’m getting into Javascript functions with parameters taking functions as parameters. I understand passing parameters, but I’ve seen the following example, or examples like it:

// Callback Function Example
function greet(name, myFunction) {
    console.log('Hello world');

    // callback function
    // executed only after the greet() is executed
    myFunction(name);
}

// callback function
function sayName(name) {
    console.log('Hello' + ' ' + name);
}

// calling the function after 2 seconds
setTimeout(greet, 2000, 'John', sayName);

It would seem to me you would call it:

setTimeout(greet('John', sayName), 2000);

But I’m pretty sure that is not right.

Can someone explain the reasoning of the parameter passing in that?

Thanks,

Russ

>Solution :

Please check the below link to have more deeper understanding of SetTimeout

setTimeout takes multiple parameters,

setTimeout(functionRef, delay, ...arguments )

functionRef : Function to be executed

delay: in milliseconds

arguments: can be any number of parameters which will passed to the function ref

https://developer.mozilla.org/en-US/docs/Web/API/setTimeout

Example:

  setTimeout((name,age,city)=>{alert(name+' '+age+' '+ city)},2000,"ABC","1","Dubai")