- Understand how functions determine scope in JavaScript
Scuber's drivers are beginning to take down some notes about their customers. Use your knowledge of scope to access and change some of these variables.
A word of warning. In this lab, you will practice doing some bad things. For
example, we'll ask you to declare variables in global scope, and write functions
that break down. You'll also need to use var to declare all variables except
when specifically instructed otherwise. We do this because, by testing the
limits and exposing the underbelly of a language, you can better understand it
and know what to avoid in the future.
Fork and clone this lab into your local environment. Navigate into its
directory in the terminal, then run code . to open the files in Visual Studio
Code.
Ok, these are your tasks:
customerName: Declare a variable in global scope calledcustomerNameusing thevarkeyword and assign it the value'bob'.upperCaseCustomerName(): Write a function that accesses that globalcustomerNamevariable, and uppercases it.setBestCustomer(): Write a function that when called, declares a variable calledbestCustomerin global scope and assigns it to be'not bob'. (Poor Bob.) Also, poor us, declaring a global variable from inside a function is one of those things we would never want to do normally, but is good for us to explore right now.overwriteBestCustomer(): See the consequences of declaring a variable in global scope, by writing a new function calledoverwriteBestCustomer()that changes thatbestCustomervariable to'maybe bob'.leastFavoriteCustomerandchangeLeastFavoriteCustomer(): Now declare a constant (using theconstkeyword) in global scope calledleastFavoriteCustomer; be sure to assign it some initial value. Finally, write a function calledchangeLeastFavoriteCustomer()that attempts to change that constant - notice what JavaScript does when you try to change the constant.
When you're done, remember to commit and push your changes up to GitHub, then submit your work to Canvas using CodeGrade.
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