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jason chan
jason chan
31,009 Points

javascript self invoking function

function adventureSelector(userChoice){
  if (userChoice == 1) {
    return function() {
      alert("You selected the Vines of Doom!");
  } else if (userChoice == 2) {
    return function() {
      alert("Looks like you want the Lake of Despair!");
  } else {
    return function() {
      alert("The Caves of Catastrophe!");
// choice one
// choice two
// everything else


// to call a function
var ad = adventureSelector(1);

so basically all you do is add () at the end of the function to create the self invoking function. Pretty cool you do not have to define a variable.

Won't that just run through the 3 functions at the end? I mean, won't that just print the following:

You selected the Vines of Doom!
Looks like you want the Lake of Despair!
The Caves of Catastrophe!


I use this to wrap my code in an anonymous function to silence the lint checker (it annoys me otherwise haha):

(function () {
  'use strict';

1 Answer

jason chan
jason chan
31,009 Points


I'm just checking if all three functions work and they do.

Ah ok! Thought there was more to it! :)