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JavaScript

jason chan
jason chan
31,009 Points
Posted by 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
adventureSelector(1)();
// choice two
adventureSelector(2)();
// everything else
adventureSelector()();

vs

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

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.

Leon Segal
Leon Segal
14,754 Points

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!

Confused!

Leon Segal
Leon Segal
14,754 Points

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

(function () {
  'use strict';
  //code
}());

1 Answer

jason chan
jason chan
31,009 Points
jason chan
jason chan
31,009 Points

Yup.

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

Leon Segal
Leon Segal
14,754 Points

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