（function（）{}）（）;和有什么区别？ 和（function（）{}（））;？

Question

Will the two following different lines of code do exactly the same?

(function(){})();

(function(){}());

Answer 1

Yes. The only reason to include parentheses around the whole expression is to avoid its interpretation as a function declaration:

(function f(){}());  // (1) Expression
(function f(){})();  // (2) Expression
function f(){}       // Function declaration
function f(){}();    // Syntax error

But whether you invoke the function literal directly (1) or have an intervening pair of parentheses (2) makes no difference at all.