Sometimes abstraction kills performance

date_range.rb

require 'benchmark'
Object.send(:remove_const, :DateRange)
class DateRange < Struct.new(:start_date, :end_date)
  def good_include?(date)
    (start_date..end_date).cover?(date)
  end
  def other_include?(date)
    (date >= start_date && date <= end_date)
  end
end

range = DateRange.new(1.year.ago, Time.now)
n = 50000
date = 10.months.ago
start_date, end_date = range.start_date, range.end_date

Benchmark.bm { |x|
  x.report { 
   n.times { (start_date..end_date).cover?(date) }
  } 
  x.report { 
   n.times { (date >= start_date && date <= end_date) }
  }
}


#       user     system      total        real
#   0.540000   0.020000   0.560000 (  0.588925)
#   0.270000   0.000000   0.270000 (  0.266373)