Does Enumerator::Lazy make loops running faster? Maybe, It depends.

enumerator-lazy-benchmark.rb

# ruby 2.1.2

require 'benchmark/ips'

Benchmark.ips do |x|
  x.report { (1..100).select { |x| x % 3 == 0 }.select { |x| x % 4 == 0 } }
  x.report { (1..100).select { |x| x % 3 == 0 && x % 4 == 0 } }
  x.report { (1..100).lazy.select { |x| x % 3 == 0 }.select { |x| x % 4 == 0 }.to_a }
end

# Calculating -------------------------------------
#   6721 i/100ms  70335.8 (±9.5%) i/s -     349492 in   5.021743s
#   7731 i/100ms  78716.6 (±8.3%) i/s -     394281 in   5.047430s
#   2565 i/100ms  26628.3 (±17.8%) i/s -    130815 in   5.075386s


Benchmark.ips do |x|
  x.report { (1..100).select { x.to_s.include?('3') }.take(10) }
  x.report { (1..100).lazy.select { x.to_s.include?('3') }.take(10).to_a }
end

# Calculating -------------------------------------
#   702  i/100ms    7259.2 (±12.7%) i/s -      35802  in   5.013737s
#   2614 i/100ms   26893.2 (±15.5%) i/s -      133314 in   5.078519s


# NEED TO RUN MORE TESTS