Deno: Callback on exit

Question

How do you add a callback for the program exiting?

Implementation in nodejs:

process.on('exit', function (){
    console.log('Goodbye!');
});

user_1119863 · Answer

You can use unload

window.addEventListener("unload", () => {
   console.log('goodbye!');
});

setTimeout(() => console.log('before goodbye'), 1000);

You can check more about Program Lifecycle here.

Unfortunately it won't be called if Deno.exit() is called. There's an open issue regarding this, and hopefully, it will be possible soon.