const obj = {
num1 : 'string',
}
const obj2 = {
num2 : 1234
}
let a = {
...obj,
}
a = {
...a,
...obj2,
}
a.num1 // ok
a.num2 // error
Object a contains first element num1 and dont show the second num2
in real code the obj and obj2 is complex and not same
