Hash vs. Array vs. Set

gistfile1.rb

require 'benchmark'
require 'set'

Document = Struct.new(:id,:a,:b,:c)
documents_a = []
documents_h = {}
documents_s = Set.new

1.upto(10_000) do |n|
  d = Document.new(n)
  documents_a << d
  documents_h[d.id] = d
  documents_s << d
end

searchlist = Array.new(1000){ rand(10_000)+1 }

Benchmark.bm(10) do |x|
  x.report('array')	{searchlist.each{|el| documents_a.any?{|d| d.id == el}} }
  x.report('hash')	{searchlist.each{|el| documents_h.has_key?(el)} }
  x.report('set')	  {searchlist.each{|el| documents_s.include?(el)} }
end