Traceback/NameError exception using SublimeText 2 with Ruby

Question

This code form RubyMonk works in RubyMonk:

class Calculator
  def add(a, b)
   a + b
  end

  def subtract(a, b)
   a - b
  end
end

I copied it to Sublime Text 2, set the build system to Ruby, then I saved it. When I type in the console something like add(1, 2) , I get the following exception:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
NameError: name 'add' is not defined

I couldn't find a solution to this. I tried reinstalling Sublime Text 2, tried the beta of ST3, tried other code which I know to be good (same error), etc., and nothing is working. Any ideas?

EDIT: On the suggestion of another user, I tried:

Calculator.new.add(1, 2)

which returned:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
NameError: name 'Calculator' is not defined

Answer 1

Sublime Text 2 console is python console, not ruby.

Additionally your ruby code is incorrect.

Answer 2

I have the sensation that you're calling the method add(1,2) for no Object at all. What I mean is, in this case, that you're not telling the Calculator to add, but just to the thin air... which does not know how to add!

Try doing th following: Calculator.new.add(1,2)

And you'll be asking an instance of the Calculator to add.

Tell me if you have any doubts or if I'm completely mistaken!

EDIT: As stated by texasbruce, ST2 console is Python. Therefore, the solution is the following: Add puts Calculator.new.add(1,2) in the code and hit Ctrl+B to launch Ruby.