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Why there is semicolon at the start of a JavaScript function?

Very often while reviewing the code for my team, I will come across a semicolon at the start of JavaScript function as show below
;
(function () {
    'use strict';
...and I often wondered what purpose it served.

Guess what. It is an insurance to make sure your script works fine when all other scripts are merged together; 

The leading ; in front of immediately-invoked function expressions (iffe) is there to prevent errors when appending the file during concatenation to a file containing an expression not properly terminated with a ;.

So there you go. Now you know what that little semicolon is doing there in your code.
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Comments

Unknown said…

thank you for sharing such a nice and interesting blog with us. hope it might be much useful for us. keep on updating...

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18 May 2016 at 07:12
Haritha said…
Really an awesome post. I wondered by reading this blog post. Thanks a lot for posting this unique post which you have shared with us. Keep on posting like this exclusive post with us.

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18 May 2016 at 07:24
debugguru said…
Thanks @Satya, @Haritha and @Kalpu for the comments. Glad my blog is helping
29 September 2016 at 20:10
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