Ruby parallel assignment benchmark

discard.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

require "benchmark/ips"

def validate
  [false, "not valid"]
end

Benchmark.ips do |x|
  x.report("ok,") do
    ok, = validate
  end

  x.report("ok, _") do
    ok, _ = validate
  end

  x.report("ok, _error") do
    ok, _error = validate
  end

  x.compare!
end

__END__
Result:

Warming up --------------------------------------
                 ok,   241.064k i/100ms
               ok, _   240.399k i/100ms
          ok, _error   238.295k i/100ms
Calculating -------------------------------------
                 ok,      6.744M (± 2.8%) i/s -     33.749M in   5.008948s
               ok, _      6.573M (± 3.3%) i/s -     32.935M in   5.017105s
          ok, _error      6.641M (± 2.9%) i/s -     33.361M in   5.028197s

Comparison:
                 ok,:  6743781.2 i/s
          ok, _error:  6640767.1 i/s - same-ish: difference falls within error
               ok, _:  6572639.0 i/s - same-ish: difference falls within error

Ruby:

    ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-darwin16]

Hardware:

    Hardware Overview:

      Model Name: MacBook Pro
      Model Identifier: MacBookPro12,1
      Processor Name: Intel Core i7
      Processor Speed: 3,1 GHz
      Number of Processors: 1
      Total Number of Cores: 2
      L2 Cache (per Core): 256 KB
      L3 Cache: 4 MB
      Memory: 16 GB
      Boot ROM Version: 180.0.0.0.0
      SMC Version (system): 2.28f7

Software:

    System Software Overview:

      System Version: macOS 10.12.6 (16G1618)
      Kernel Version: Darwin 16.7.0
      Time since boot: 10 days 6:31