Structure of Ruby Programs

Question

I need some insight into the construction of Ruby programs. I'm trying to learn how to write Ruby (independent of Rails) so I'm translating some Perl scripts I wrote in a bioinformtatics project into Ruby code. Basically creating classes where useful and whatnot.

My issue is how do I execute it? The Perl scripts are just long blocks of commands, one after the other. What's appropriate in Ruby? Should I define my classes in their own .rb files and call those and their methods in a sepearate rb file that sort of uses them to execute my program?

What is normally done? Any examples would be greatly apreciated. I'd also appreciate any tips in general on how to go about learning this kind of thing.

Answer 1

Ruby does have what's usually called the top level execution environment, and so a long string of commands will execute immediately just like Perl. Or, you can define classes and modules and go all OOP on your problem if you want, or you can mix the approaches.

You will need at least one line at the top level or top level of a class to start everything off. So:

p :hello

or

class A
  p :hello
end

or

class A
  def run
    p :hello
  end
end
A.new.run

or, my favorite:

class A
  def run
    p :hello
  end
  self
end.new.run

Answer 2

I'd highly recommend looking at some of your other favorite gems to see how their code is structured (like on Github). That's how I found my start. Thinking of your project as a "gem", being released or not, is a good way to wrap your mind around the problem.