Week 6 Day 1: In Sinatraland, facing the Bridge to Railsabithia

Major Activities of the Day: We started with a straightforward TODO where we create a class that takes in a number and breaks it down into binary ones and zeros, and generates a list from a constant array based on which values were ones.  Well, I said it's straightforward, but the implementations ranged a lot.  Here was my solution - I couldn't figure out anything simpler, so I'm relatively certain it can't be done in any cleaner way:


In this case, 1 represented eggs, 2 represented peanuts, etc., all the way through 128 for cats.  I used the handy [n] method (which I discovered accidentally while doing the lab, trying to use the similarly-syntaxed method for Strings), which works on Fixnum integers (but not on Bignum integers!) and returns the 1 or 0 which is n digits from the end. So for the number 11, which is 1011 in binary, you would get:
11[0] #=> 1
11[1] #=> 1
11[2] #=> 0
11[3] #=> 1


After that activity, we moved on to a lab where we put together a Sinatra web app with lots of relationships between models - ponds with frogs with tadpoles.  Then we moved on to our first lecture about Rails.  Avi demonstrated the power of Rails generators by doing a bunch of stuff manually, then doing it all over again in a command or two.  Finally, since we haven't yet covered enough Rails to do useful things yet, we instead returned to Sinatra to put together a web app to store songs, artists, and genres, where each song has one artist and multiple genres, and artists and genres can access each other through songs.  (Technically we could have used a join table between artists and genres, but I felt that would mean a lot of database maintenance when instead it makes more sense to create a has_many through relationship between artists and genres, through songs.

Skills Developed: Working with binary numbers, assembling complex relationships in Sinatra apps, and a slight glimmer of Rails