Javascript constructor functions different patterns -

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• javascript why wrap variable or constructor in iife? 2 answers

what's difference between 2 code snippets below. understand second 1 uses iife, unable understand what's benefit of 1 on other. can please explain.

//first******* var student=function student(name) {     this.name = name; } student.prototype.printmessage = function () {     console.log(this.name); }; var st = new student("test"); st.printmessage();  //second** var student = (function () { function student(name) {     this.name = name; } student.prototype.printmessage = function () {     console.log(this.name); }; return student; }()); var st = new student("test"); st.printmessage(); 

in simple example, there no advantage using iife. purpose of such construction if had variables other student didn't want expose global scope.