/ / Please paste the code text below (do not replace the code with pictures)
var obj = {a:1};
function fun (obj){
obj = {a:2}
}
fun(obj)
console.log(obj) Why is the output {avl 1}? Shouldn"t the obj in the
function be promoted as a global variable without a var declaration?
var obj = {a:1};
function fun (obj){
console.log(arguments);
obj = {a:2}
}
fun(obj)
console.log(obj)try this and you'll see
the expression obj is a formal parameter, which is valid only within the function and does not affect the obj outside the function
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