Question

Let’s say I have 4 characters, A, P, B, N. I want to be able to compare them such that:

A > P > B > N > A

How would this be accomplished in Ruby?

Answer 1

From your comments, it seems that you are not trying to put these elements in order, but rather define some binary relation between some of them. It’s possible to do that in Ruby in many ways, depending on how you intend to use that relation later.

The simplest one is just to define ordered pairs of related elements:

MAP = [
  ['A', 'P'],
  ['P', 'B'],
  ['B', 'N'],
  ['N', 'A']
]

And then use it whenever you need to “compare” two elements.

def beats? one, other
  MAP.member?([one, other])
end

beats? 'A', 'B'
# => false 
beats? 'A', 'P'
# => true 
beats? 'N', 'A'
# => true 

PS. You can generate the map from a string using something like

MAP = 'APBNA'.chars.each_cons(2).to_a