require 'benchmark/ips'

def fizzbuzz_method
  return to_enum __method__ unless block_given?
  n = 0
  loop do
    n += 1
    if (n % 15).zero?
      yield 'FizzBuzz'
    elsif (n % 5).zero?
      yield 'Buzz'
    elsif (n % 3).zero?
      yield 'Fizz'
    else
      yield n
    end
  end
end

p fizzbuzz_method.take 50

fizzbuzz_enum = Enumerator.new do |yielder|
  n = 0
  loop do
    n += 1
    if (n % 15).zero?
      yielder.yield 'FizzBuzz'
    elsif (n % 5).zero?
      yielder.yield 'Buzz'
    elsif (n % 3).zero?
      yielder.yield 'Fizz'
    else
      yielder.yield n
    end
  end
end

p fizzbuzz_enum.take 50

fizzbuzz_lazy = (1..Float::INFINITY).lazy.map do |n|
  if (n % 15).zero?
    'FizzBuzz'
  elsif (n % 5).zero?
    'Buzz'
  elsif (n % 3).zero?
    'Fizz'
  else
    n
  end
end

p fizzbuzz_lazy.first 50

Benchmark.ips do |bm|
  bm.report 'Method' do
    fizzbuzz_method.take 50
  end

  bm.report 'Enumerator' do
    fizzbuzz_enum.take 50
  end

  bm.report 'Lazy' do
    fizzbuzz_lazy.first 50
  end

  bm.compare!
end