The JavaScript Interview Handbook: 100+ Interview Questions/

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Solution Review: Shallow Copy

Solution Review: Shallow Copy

In this lesson, we will discuss the solutions to the questions in the previous lesson.

We'll cover the following...

Question 1: Solution review #

In the previous lesson, you were given the following code:

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const girl = {
  name: 'Anna',
  info: { age: 20, number: 123 }
};
const newGirl = { ...girl };
newGirl.info.age = 30;
console.log(girl.info.age, newGirl.info.age);

For the code above, you had to answer the following question:

Explanation #

Run the code below to see the output:

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const girl = {
  name: 'Anna',
  info: { age: 20, number: 123 }
};
const newGirl = { ...girl };
newGirl.info.age = 30;
console.log(girl.info.age, newGirl.info.age);

As you can see, Option C is the correct answer. Let’s discuss why.

There is an object, girl, that has properties name and info. On line 6, we copy the properties of the girl object into the newGirl object using ...