Question

I’m just trying a simple callback to get code to execute in order instead of asynchronously. This does not work:

function fn1(string, func){
    console.log("hello");
    func();
};

function fn2(){
    console.log("world");
}

fn1("meaninglessString", fn2());

It actually print “world” then “hello” to the console then crashes. But this does:

function fn1(string, func){
    console.log("hello");
    func();
};

fn1("meaninglessString", function(){
    console.log("world");
});

Do I have to always write the callback function code right in the call to fn1 or is there a way to reference an already-written function? Also, is this the best way to be doing this in Node.js if I just want one function to happen after another has finished?

Answer 1

Take a look at your last line:

fn1("meaninglessString", fn2());

it should be the following instead:

fn1("meaninglessString", fn2);

Including the parenthesis causes fn2 to be executed immediately.