Location of parenthesis for auto-executing anonymous JavaScript functions?

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They’re virtually the same.

The first wraps parentheses around a function to make it a valid expression and invokes it. The result of the expression is undefined.

The second executes the function and the parentheses around the automatic invocation make it a valid expression. It also evaluates to undefined.

I don’t think there’s a “right” way of doing it, since the result of the expression is the same. 

> function(){}()
SyntaxError: Unexpected token (
> (function(){})()
undefined
> (function(){return 'foo'})()
"foo"
> (function(){ return 'foo'}())
"foo"

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