what means this javascript code function -

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• what (function() { } )() construct in javascript? 19 answers

(function () {     // somethig })(); 

what means function in parentheses? ()(); developers creates functions in js files directly.

what means function in parentheses? ()();

that means self-invoking function in javascript.

notice the: (); - calling.

your function, anonymous btw, invoked automatically without caller intervention, itself, once it's declared.

in addition, @thilo suggested, isolated scope local variables.