for example:
let obj = {
name: {
first: "Hello",
last: "World"
},
age: 20
}
let objx = new Proxy(obj, {
set(target, key, value, receiver) {
console.log(key);
target[key] = value;
}
})
objx.age = 18;
objx.name.first = "Hello!";
in this case, only objx.age, cannot listen for changes to the objx.name.first attribute
you need to traverse the object deeply, and then proxy each object
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