present.rb

#!/usr/bin/env ruby -w
require "rubygems"
require "benchmark"
require "active_support"

TIMES = 10_000_000

class Project
  attr_reader :ivar

  def initialize
    @ivar = nil
  end

  def check_with_cast
    ivar ? true : false
  end

  def check_with_present
    ivar.present?
  end
end

project = Project.new

Benchmark.bm(30) do |b|
  b.report "check_with_cast" do
    TIMES.times do |i|
      project.check_with_cast
    end
  end

  b.report "check_with_present" do
    TIMES.times do |i|
      project.check_with_present
    end
  end
end

__END__
                                    user     system      total        real
check_with_cast                 3.520000   0.000000   3.520000 (  3.548733)
check_with_present              6.640000   0.000000   6.640000 (  6.669177)