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Liwei Xu
3,323 PointsWhy doesn't this var conflict with the const in this function?
'use strict';
(function () { const student = { name: 'James' };
function createStudent(name) { const student = { name: name }; return student; }
console.log(createStudent('Ken')); console.log(student); })();
I tried it in chrome dev tool and it didn't generate an error of "student is already assigned"? like the video about duplicate variables talked a bout?
Thank yoU!
1 Answer
gyorgyandorka
13,811 PointsIn JavaScript, variables created with var inside of a function are "scoped" to that function, meaning they can only be reached from inside that function, other parts of the program do not "see" them. This also applies to nested functions - the outer function doesn't see what's going on in the inside one, you can define variables with the same name without problems.
The same applies to let and const, but they are scoped not only to the nearest function, but, more generally, the nearest curly brace-separated enclosing block (like a loop or an if-statement inside a function).