Javascript - what is the purpose of wrapping functions or codes in a function?

Question

This probably is not a new question, but where is the purpose of wrapping a function or codes inside ((function () {...})());? for instance,

//Self-evoking anonymous functions
((function () {

    alert("hi");

})());

What's the difference with no wrap,

alert("hi");

I still get the same result - hi

What can you pass/ put in the brackets in the end bit - })());? and why?

Read this http://blog.nitishkumarsingh.com/javascript-anonymous-functions/ — Nitish Kumar, Jan 09 '15 at 06:56

score 1 · Accepted Answer · answered Jan 09 '15 at 06:57

Using a function creates a scope. You can have params inside and do more than just alerting.
Now you can do the same without a function, but then you will keep the state on the window object and thats something that you would like to prevent in some cases.

Javascript - what is the purpose of wrapping functions or codes in a function?

1 Answers1