array-bench.rb

require 'benchmark'

Test = Struct.new(:value)

def contains(a, b)
  a.any? do |n|
    b.include?(n)
  end
end

Benchmark.bm do |x|
  a = (0..10000).map { |i| Test.new(i) }
  b = [Test.new(1000), Test.new(99999)]
  
  x.report("early match, intersect") { (a & b).any? }
  x.report("early match, loop") { contains(a, b) }
end

Benchmark.bm do |x|
  
  a = (0..10000).map { |i| Test.new(i) }
  b = [Test.new(99999)]
  
  x.report("no match, intersect") { (a & b).any? }
  x.report("no match, loop") { contains(a, b) }
end