nsteps the rubyway.

nsteps.rb

# this has only one side effect, it defines the nsteps fmethod
def nsteps(x, y)
  if (x.even?)
    return false if(y.odd?)
    return x * 2 if(x == y) 
    return x * 2 - 1 if (x==(y-2))
    return false
  else 
    return false if(y.even?)
    return x * 2 if(x == y) 
    return x * 2 - 1 if (x==(y-2))
    return false
  end
end

# this has no side effects effects 
lambda do |x, y|
  if (x.even?)
    return false if(y.odd?)
    return x * 2 if(x == y) 
    return x * 2 - 1 if (x==(y-2))
    return false
  else 
    return false if(y.even?)
    return x * 2 if(x == y) 
    return x * 2 - 1 if (x==(y-2))
    return false
  end
end.call(1, 3)