Ironyard Exercises

EXTRA CREDIT (added 3/5/15)

In JavaScript, given a set of arrays, write a program that will tell me which arrays contain all the members of the other array:

var array1 = [
  { name: 'John', age: 25},
  { name: 'Jane', age: 58},
  { name: 'Josh', age: 12}
]

var array2 = [
  { name: 'Jane', age: 58},
  { name: 'John', age: 25}
]

var array3 = [
  { name: 'John', age: 25},
  { name: 'Jane', age: 58}           
]

In this case array2 and array3 are the same but in a different order, but array1 is not fully contained within array2 (missing Josh). An example API might look like:

array1IsASubsetOf(array2) // false
array2IsASubsetOf(array3) // true
array2IsASubsetOf(array1) // true

Write this program in less than five lines of (readable, less than 80 columns wide) code with underscore as the only dependency and I will buy you lunch (limit 2 first successful attempts). While the main assignment is intended to be done in groups, this is a solo effort and I will ask for your answers on Tuesday. Thanks! See you then.

Homework for Jed's lecture on Functional Programming

How To

Functional Programming is a different way of thinking than Procedural or Object Oriented programming. Spend some time learning how these three styles differ (wikipedia might be a great start) and do your best to try to implement these as described below.

It turns out that Ruby can be more functional (like LISP) than you might think .

solve the problem in Ruby (you need MiniTest installed gem install minitest)
- in an imperative/procedural fashion
- in a functional fashion (hint: use the Eunumerable module)
- in an object oriented fashion
solve the problem in JavaScript (uses the jasmine-node testing framework—see Running JS Tests below)
- to the best of your ability without dependencies
- with Underscore as a utility library

Solutions have been given, but it doesn't mean they are the best solutions. My advice is to delete the file contents and work your way through the problems yourselves. (I hear Nick is giving creativity points.)

Yes, you may work in groups. No the homework is not graded, but you won't get much out of the lecture if you have not done this prep and that would be a waste of time for me and you. If you work with others, be sure you understand the language decisions made.

Running JS Tests

If you don't have npm installed, run $ brew install npm.
Install jasmine-node. To install it globally, run $ npm install -g jasmine-node.
To run the tests:

From inside anagram_javascript, run $ jasmine-node .
From inside anagram_coffeescript, run $ jasmine-node . --coffee.

Discussion

Come to the lecture 9/19 ready to discuss the following questions.

What solution in Ruby do you like best? Why?
Are there patterns from your Ruby solutions that lend themselves to JavaScript solutions?
Are there conveniences in Ruby you wish you had in JavaScript? Why?

Feedback/Questions

Open a github issue. I'll gladly answer any questions.

Credits

Both problems take from exercism.io but problems in that application are served rather than picked so this just uses a problem that is solved in roughly equal terms in several languages.

tnez/ironyard_exercises