| ####### Submission for Hamming Exercism Problem ######### | |
| class Hamming | |
| def self.compute(strand, comparison_strand) | |
| return 0 if strand == comparison_strand | |
| strand_array = strand.split(//) | |
| comparison_strand_array = comparison_strand.split(//) | |
| compute_difference(strand_array, comparison_strand_array) | |
| end | |
| def self.compute_difference(strand_1, strand_2) |
| require 'date' | |
| require 'time' | |
| class Gigasecond | |
| GIGASECONDs_IN_DAYS = 10**9 / (60 * 60 * 24) # 1 day = 86,400 seconds | |
| def self.from(date) | |
| date + GIGASECONDs_IN_DAYS | |
| end |
| module Complement | |
| DNA_TO_RNA_MAP = { | |
| 'A' => 'U', | |
| 'C' => 'G', | |
| 'G' => 'C', | |
| 'T' => 'A' | |
| } | |
| RNA_TO_DNA_MAP = DNA_TO_RNA_MAP.invert |
| ########## Raindrops Exercism Problem ############## | |
| class Raindrops | |
| class << self | |
| def convert(number) | |
| add_sounds(number) || number.to_s | |
| end | |
| private |
| 1. Explain how helpers improve the readability and organization of your rails app. | |
| View helpers allow you to extract logic from your views in order to keep them as simple as possible. They improve the readability of view templates in several ways: | |
| - Replacing complicated logic with a call to a helper method eliminates a lot of code from the view template itself. In addition, the code that remains in the view template is focused on the view layer, namely HTML elements and ERB tags consisting of calls to view helpers and objects from the controller. | |
| - The purpose of the view helper can be expressed by the name you choose. For example, a view helper that displays admin controls can be encapsulated in a method named, "admin_controls". The purpose of the method is clear from its name. If you instead put all the logic to determine whether a user is an admin and then conditionally display elements, the purpose of the code would be difficult to comprehend. | |
| In addition to making the view templates easier to read, |
| 1. Demonstrate the command to list all the rake tasks, and the one to match a particular set of tasks. | |
| rake -T | |
| 2. Explain what sorts of tasks (including examples) belong in a rake task. | |
| Tasks that belong in a rake task include jobs that should be performed on the command line, and not through the UI. Administrative tasks involving assets, the database, documentation, routes, temporary files, and performing batch processes, such as updating database records or sending out emails, are all viable rake tasks. |
| Exercise: Knows the location and conventions for Rspec and Cucumber | |
| 3. Explain the usage of integration versus unit tests in your Rails app. | |
| Integration tests in a Rails app will test the functionality of an entire Feature. This will normally test the entire response cycle--from the initial request, to the controller, models, views and then the response returned to the browser. Unit tests, in contrast, focus on testing one method or interaction in one particular class in the app. This could be a model, helper, controller or view. They are much more focused than integration tests. | |
| 4. There is a default command that is used in normal Rails codebases to run all tests. What is it? | |
| "rake" will run all tests | |
| "rake spec" will run all tests in the spec directory |
Write a function to convert from normal numbers to Roman Numerals: e.g.
The Romans were a clever bunch. They conquered most of Europe and ruled it for hundreds of years. They invented concrete and straight roads and even bikinis. One thing they never discovered though was the number zero. This made writing and dating extensive histories of their exploits slightly more challenging, but the system of numbers they came up with is still in use today. For example the BBC uses Roman numerals to date
| 1. Explain what it means that 'everything has an API'. | |
| "Everything has an API" is the notion that an API is more than the common usage of an interface to produce and consume data between two web services. APIs also exist within programs, gems, libraries, and classes, among other constructs. An API is the interface that defines how any two software programs interact. This could, for example, be between a Ruby Gem and the Ruby Array library. When the Ruby gem calls #sort on an Array object, it is interacting with the API of the Array library. In object-oriented programming, the core concept is that messages are passed between objects; it is the API that defines the boundaries of those objects and how they interact. APIs exist everywhere in programming, from the common usage of a web application API, such as the Google Maps API, to the many Rails APIs to the API of a small program. | |