Print Integers 1 to N without loops and conditions

1toN.rb

#!/usr/bin/env ruby

def upto_n(n)
  e = Enumerator.new do |y|
    f = -> (x) { yield x; y << x; f[x + 1] }
    f[1]
  end

  e.take(n)
end

# ------ main ------

n = ARGV[0]&.to_i

upto_n(n) { |x| puts x }

1toN2.rb

#!/usr/bin/env ruby

def upto_n(n)
  f = lambda do |x|
    yield x

    begin
      _dangerous = 1 / (n - x)

      f[x + 1]
    rescue ZeroDivisionError
      # quit recursion on error
    end
  end

  f[1]
end

# ------ main ------

n = ARGV[0]&.to_i

upto_n(n) { |x| puts x }