Hi! The purpose of these notes is to help you install and configure some software that we'll use to, well, make other software. ^_^ Here's a short list of what we'll be installing. Detailed instructions for each item follow. It is really, really important to install everything in this list. It may feel a little tedious, but getting it done now will set you up for success on day 1 (and day 100!) of class.
- OS X El Capitan (or OS X Sierra)
- Xcode Command Line Tools
- Google Chrome (web browser)
- Atom (text editor)
- Ruby Version Manager (rvm) (package manager)
- Ruby 2.3.0
OS X is the name of the operating system found on Apple computers. Apple likes to give the versions of their operating systems odd names. They used to be big cats (Cheetah, Puma, Jaguar, Panther, Tiger, Leopard, Snow Leopard, Lion, and Mountain Lion). Now it's... I don't even know. Anyway, the two most recent versions are Sierra and El Capitan. For Ada, your computer must be running one of these two versions of OS X, with preference given to El Capitan.
To check your version of OS X, click the Apple icon at the far left edge of toolbar at the top of the screen. From there, choose About This Mac. That'll open a window with lots and lots of information about your computer. Right at the top, in big type, is the current version of OS X.
If your Mac isn't running Sierra or El Capitan, please use the App Store to update. You can open the desktop App Store by going back to the Apple menu and selecting App Store.... Operating System upgrades are free, and Apple's got a detailed guide on updating.
Xcode is the name of the collection of software tools used to create programs for OS X and iOS (the operating system on Apple's mobile devices like the iPhone and iPad). We'll need some parts of Xcode, but not the whole thing. The part we need is called the Xcode Command Line Tools. We won't be using them during the Jumpstart curriculum, but it makes sense to install them now. They can take a long time to download and install, so doing it now will save us lots of time in the classroom later.
We'll use the Terminal to install the Command Line Tools. Open Terminal and start the installation by typing $ xcode-select --install. Follow the instructions and wait for the installation to finish (Protip: have a snack and maybe go for a walk while it's downloading and installing).
After it finishes, verify the installation by typing xcode-select -p. It should respond with something very similar to /Library/Developer/CommandLineTools (the directory where they were installed).
If you're reading this, you're already using a web browser (software used to access and visualize information on the internet). Unless you've intentionally switched, you're using Apple's web browser, Safari. There's nothing wrong with Safari; it's a fine browser. However, there are a few things that Google's competing browser, Chrome, can do for developers that makes for super fun times in the Ada classroom. You don't have to switch to Chrome for all your day-to-day internet use; I'd just like for you to have it available when we're in class.
To install Chrome, download it from Google's website. Open the downloaded application package and follow the instructions to complete the installation.
Writing software requires software! Way back when, writing software required stacks of thin balsa wood or cardstock cards, but these days we use a text editor instead. Word processors are software tools geared towards making composition of prose easier. Text Editors are programs geared towards making code generation easier.
For Ada, we'll use Atom. From the website, download the installer package. Then run the installer. There's not much to Atom out of the box, but it's enough to get us started writing code in the next lesson.
Note: Many folks in the Ruby sphere use either Atom or Sublime Text as their primary editor. Either is fine for the classroom, but if you don't already have Sublime Text or any other text editor, go with Atom.
Homebrew Package Manager makes it easy to install a variety of software packages, and is used by the following Ruby Version Manager (rvm).
Installing Homebrew involves copying and pasting /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
You may need to enter your computer password to complete the installation.
Run $ brew doctor. Brew is super great at telling you what else it may need. Sometimes there are file permissions to fix. Sometimes there's a warning that can be ignored. If there's anything ever wrong with Brew, brew doctor will usually be able to tell you what it is and how to fix it.
Ruby Version Manager (rvm) makes it easy to install, manage, and switch between Ruby versions. rvm is a package manager; it's software to help us install other software. Most package managers are just for installing, updating, and removing software packages, but rvm has a lot of really useful features specifically for working with Ruby that we'll use throughout Ada.
Installing rvm is done in the Terminal: $ \curl -sSL https://get.rvm.io | bash -s stable
The installation won't take long. When it's done, close your Terminal (⌘-Q) and then reopen it. You can find the ⌘ or 'Command' key next to your spacebar. On a Mac pressing both command and 'Q' will quit the active application.
Verify all's well by running $ rvm -v. You should see something like rvm 1.28.0 (latest).
Finally! Whew! Ruby is the first programming language we'll learn in the classroom. It's also my personal favorite, but that's just a happy accident.
Now that we've got rvm handy, we can install Ruby by typing the following into our terminal: $ rvm install 2.4.1
Installing Ruby can take awhile, so feel free to take a break or go for a walk while rvm gets things sorted. In short, rvm will download the ruby version you specified (2.4.1), compile it (prepare it to work specifically on your computer's hardware), install the compiled code in the right place, and do some housekeeping in the (really likely) chance you'll encounter/create code that requires a different Ruby version.
When it's done, you can verify that everything succeeded by typing $ ruby -v into your terminal. The return should say something like ruby 2.4.1p111 (2017-03-22 revision 53290) [x86_64-darwin16].
Awesome! Your environment is ready to go! In the next lesson, we'll put that environment to good use and write our first program!