js-data-structures-objects-lab-online-web-pt-041519's Introduction

Objects Lab

Problem Statement

We covered the concepts of Objects in JavaScript. Now it's time to put the concepts into practice.

Learning Goals

Create Objects
Perform operations on Objects

Instructions

Follow the steps below, running learn as you go to get additional information from the tests. To start, define a driver variable and assign it to an Object. Various updates will be applied to this variable (destructively and non-destructively) in this lab.

You'll be writing four functions:

updateDriverWithKeyAndValue()- this function should take in three arguments: a driver Object, a key and a value. This function should not mutate the driver and should return a new driver that has an updated value for the key passed in.
destructivelyUpdateDriverWithKeyAndValue() - this function should work the same as updateDriverWithKeyAndValue() but it should mutate the driver parameter passed in.
deleteFromDriverByKey() - this function should take in a driver Object and a key. It should delete the key/value pair for the key that was passed in from the driver Object. This should all not actually mutate the driver passed in.
destructivelyDeleteFromDriverByKey() - this function should work the same as deleteFromDriverByKey() but it should mutate the driver passed in. Be sure and consider whether dot-notation or bracket-notation might affect your solution.

HINT: You might find deleteFromDriverByKey() to be a bit hard to write non-destructively. Think about how we learned to use Object.assign(). What happens if we do this:

const obj = { foo: "bar" };

const newObj = Object.assign({}, obj);

newObj;
// => { foo: "bar" }

delete newObj['foo'];
// => true

newObj;
// => {}

obj;
// => { foo: "bar" }