Coursera Rails Module 2 Notes

August 12, 2016 | ruby | programming | learning |

Intro to Ruby

This module goes through a general introduction to Ruby. One thing that I find interesting is how optimistic Ruby is, in the sense that everything except for false and nil is true. This is especially interesting from the perspective of comparing true and false in sqlite where sqlite stores 0 as false and 1 as true. I have not had to deal with this yet, but it is nice to keep in mind going forward. Another nice thing that I have not used that much is irb this is basically a Ruby repl that allows you to quickly test out concepts in your shell. I also love (since I work at a CI company) that the very first lesson about ruby talks about rspec and even has us use it go grade our assignments. It is never too early to start thinking about tests.

Tour of Ruby Data Types

The next module took a nice tour of Ruby data types. I learned some pretty neat things.

Strings in Ruby super expressive, string interpolation is pretty amazing and very clean. Destructive Methods Have !, I like this convention, you see it a lot in Clojure.
%w can make multiple strings into an array (like using .split() in JS)
You can get a random element from an array with .sample, pretty neat
Hash Order is maintained, this is really powerful

I also finally understand how blocks in Ruby (closures) work. (After many years of derping through Vagrantfiles)

Object Oriented Ruby

All methods public by default
Clean class creation with useful helper methods for getter/setter
Talked about how most of the functionality in Collections comes from using the Enumerator mix-in, gave an example of how to use it, super powerful!

Unit Testing

Again, I love that this course started right off the bat talking about unit testing. A+ to the course creators for covering this topic. The instructor did a good job talking about the differences between Test::Unit, MiniTest, and RSpec with great examples of how to use all of them.

Assignment

The final assignment for this module was to write a program that reads a file and calculates word frequency. Overall it was pretty simple, I think the material did a good job preparing us for the task, and caused us to use a lot of the different tools that we learned about Ruby.

Parting Thoughts

I have often heard that Ruby was designed for developer happiness. I really love the clean syntax, well documented API, and elegance. The next module will be a deep dive into Rails, looking forward to using more of the stuff that I have learned in this Ruby crash course.

Thank you for reading! Share your thoughts with me on bluesky, mastodon, or via email.

Check out some more stuff to read down below.

Most popular posts this month

Recent Favorite Blog Posts

This is a collection of the last 8 posts that I bookmarked.

Fedora Magazine: Contribute to Fedora 44 KDE and GNOME Test Days from Fedora People
Pluralistic: bunnie's piggyback hack (09 Jan 2026) from Pluralistic: Daily links from Cory Doctorow
Clicks Communicator from Chris Hannah
A Year Of Vibes from Armin Ronacher's Thoughts and Writings
Pluralistic: A perfect distillation of the social uselessness of finance (18 Dec 2025) from Pluralistic: Daily links from Cory Doctorow
Moving from WordPress to Substack from charity.wtf
Grow, Like a Tree Not a Cancer from Jim Nielsen’s Blog
Pluralistic: All the books I reviewed in 2025 (02 Dec 2025) from Pluralistic: Daily links from Cory Doctorow

Articles from blogs I follow around the net

Doing less, for her

My daughter will be born soon, and I’m reflecting on what that means for my OpenSource work.

via Carlos Becker February 1, 2026

The Browser’s Little White Lies

So I’m making a thing and I want it to be styled different if the link’s been visited. Rather than build something myself in JavaScript, I figure I’ll just hook into the browser’s mechanism for tracking if a link’s been visited (a sensible approach, if I d…

via Jim Nielsen’s Blog February 1, 2026

$29 million stolen from from Step Finance treasury wallets

The Solana-based defi portfolio tracker Step Finance lost 261,854 SOL (~$28.7 million) when a thief gained access to treasury and fee wallets. It's not yet clear how the attacker was able to steal the funds, although Step Finance…

via Web3 is Going Just Great February 1, 2026

Generated by openring