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@speric
speric / poodir-notes.md
Last active May 15, 2024 13:39
Notes From "Practical Object-Oriented Design In Ruby" by Sandi Metz

Chapter 1 - Object Oriented Design

The purpose of design is to allow you to do design later, and it's primary goal is to reduce the cost of change.

SOLID Design:

  • Single Responsibility Principle: a class should have only a single responsibility
  • Open-Closed Principle: Software entities should be open for extension, but closed for modification (inherit instead of modifying existing classes).
  • Liskov Substitution: Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program.
  • Interface Segregation: Many client-specific interfaces are better than one general-purpose interface.
class MegaLotto
NUMBERS = 5
def draw
NUMBERS.times.inject([]) do |arr, i|
arr << single_draw
end
end
private
@ryansobol
ryansobol / gist:5252653
Last active November 4, 2024 23:06
15 Questions to Ask During a Ruby Interview

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.