Why is this javascript object with simplest constructor undefined? -


i tested in console : 

var toto = (function() {function toto() {}})(); toto

result in chrome console 

undefined

why ? have expected usual constructor :

function toto() {}

what syntax error did make ?

if run code believe give answer.

var noname = (function() {     function toto() {          console.log('running toto');          return 'returning toto';     }     console.log(toto());     return 'no name'; })(); console.log(noname);

the longer answer following.

(function(){})();

this called iife (immediately invoked function expression) creates , calls function right after created. place in it, contained function. best way create private variables in es5 javascript. functions can return things iife , access variables declared outside iife nothing within outside, again creates private scope. have iife return nothing returns default value undefined.


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