Why does an IIFE that appears after an object literal expression throw an error?

Question

I'm defining various modules in a JavaScript file:

var module = {/* ... */}

(function(){
    console.log('Invoked');
})()

However the IIFE throws an error:

TypeError: object is not a function

I tried copy and pasting just the IIFE code and there is no issue.

Answer 1

The module definition needs a semicolon at the end of the declaration:

var module = {/* ... */}; // <======= Semicolon!

(function(){
    console.log('Invoked');
})()

Without it Javascript is trying to call the object:

var module = {/* ... */}(function(){console.log('Invoked');})()

Or shortened:

var module = {/* ... */}()

You'd get the same problem when trying to writing two IIFEs next to each other:

(function(){})()
(function(){})()

This doesn't work because a single function declaration returns undefined:

TypeError: undefined is not a function