javascript - (function(){})() vs. !function(){}() -

this question has answer here:

• what exclamation mark before function? 7 answers

in jquery javascript code see

(function(window, undefined) { })(window); 

and in twitter

!function(window, undefined) { }(window); 

can tell difference between these 2 approaches is?

using ! operator before function causes treated expression, can call it:

!function() {}() 

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