shallow Copy, Deep copy and copy by reference

shallow-copy.js

let obj = {a:'b', c:{d:'e', f:{g:'h'}}}

let obj1 = {...obj}

// let obj2 = obj

// let obj1 =  Object.assign({}, obj)


obj1.a = 'b1'
console.log(obj, ":", obj1);

// obj.c.d = 'e2'

// console.log(obj, ":", obj1);


// obj1.c.f.g = 'h2'

// console.log(obj, ":", obj1);

/**
 What are we seeing here is the example of shallow copying an object. What it means that if you change the value of any key it will not reflect
the changes in the original object. But if you try  to change the nested object's key. The changes will also reflect in the original object.
The reason is `{d:'e', f:{g:'h'}}` the nested part is stored somewhere and both the original object obj and obj1 keep the reference of it, not as actual value

In simple what actually happened herer
let obj = {a:'b', c:{d:'e', f:{g:'h'}} }
is simply executed like this
let objf' = {g:'h'}
let objc' = {d:'e', f:objf'}
let obj = {a:'b', c:objc' }

Means obj has ther reference of objc' and f in objc' has the reference of {g:'h'}

 */