haml-static.rb

#!/usr/bin/env ruby
require 'benchmark/ips'
require 'haml'

t1 = 1000.times.map do |i|
  "%span{foo: #{i}}"
end.join("\n")

t2 = 1000.times.map do |i|
  "%span{:foo => #{i}}"
end.join("\n")

t3 = 1000.times.map do |i|
  "%span{foo: '#{i}'}"
end.join("\n")

t4 = 1000.times.map do |i|
  "%span{:foo => '#{i}'}"
end.join("\n")

obj = Object.new
Haml::Engine.new(t1).def_method(obj, :t1)
Haml::Engine.new(t2).def_method(obj, :t2)
Haml::Engine.new(t3).def_method(obj, :t3)
Haml::Engine.new(t4).def_method(obj, :t4)

puts "Haml::VERSION #{Haml::VERSION}"
Benchmark.ips do |x|
  x.report('t1') { obj.t1 }
  x.report('t2') { obj.t2 }
  x.report('t3') { obj.t3 }
  x.report('t4') { obj.t4 }
  x.compare!
end

__END__

Haml::VERSION 4.0.6
Calculating -------------------------------------
                  t1     5.000  i/100ms
                  t2     5.000  i/100ms
                  t3     5.000  i/100ms
                  t4     3.300k i/100ms
-------------------------------------------------
                  t1     56.953  (± 1.8%) i/s -    285.000 
                  t2     57.075  (± 1.8%) i/s -    290.000 
                  t3     56.769  (± 1.8%) i/s -    285.000 
                  t4     40.728k (± 6.9%) i/s -    204.600k

Comparison:
                  t4:    40728.0 i/s
                  t2:       57.1 i/s - 713.59x slower
                  t1:       57.0 i/s - 715.11x slower
                  t3:       56.8 i/s - 717.43x slower