An ambiguous case that breaks in the absence of a semicolon:
// define a function
var fn = function () {
//...
} // semicolon missing at this line
// then execute some code inside a closure
(function () {
//...
})();
This will be interpreted as:
var fn = function () {
//...
}(function () {
//...
})();
We end up passing the second function as an argument to the first function and then trying to call the result of the first function call as a function. The second function will fail with a "... is not a function" error at runtime.
