require 'benchmark/ips'

class A
  def sum
    1 + 1
  end
end

class B
  def sum
    eval("1 + 1")
  end
end

class C
  define_method(:sum) {
    1 + 1
  }
end

class D
  def sum
    Proc.new { 1 + 1 }.call
  end
end

class E
  def sum
    -> { 1 + 1 }.call
  end
end

Benchmark.ips do |x|
  x.config(:time => 20, :warmup => 2)

  x.report("Using method") do
    A.new.sum
  end

  x.report("Using eval") do
    B.new.sum
  end

  x.report("Using define_method") do
    C.new.sum
  end

  x.report("Using proc") do
    D.new.sum
  end

  x.report("Using lambda") do
    E.new.sum
  end

  x.compare!
end