Ruby Batteries Included

Transcript

1. RUBY BATTERIES INCLUDED Ruby Can Standard Library, And So Can

   You!

2. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP?

3. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP?

   $ grep gem Gemfile -c

4. HOW MANY GEMS DOES IT TAKE TO BUILD AN APP?

   $ grep gem Gemfile -c 135

5. THE STANDARD LIBRARY http://ruby-doc.org/

6. CORE VS STD-LIB

7. find `ruby -e 'puts $:.join(" ")'` -iname '*.rb' -exec grep

   -E '^\w*class ' {} \; | sort | uniq | wc -l

8. find `ruby -e 'puts $:.join(" ")'` -iname '*.rb' -exec grep

   -E '^\w*class ' {} \; | sort | uniq | wc -l

9. OKAY, NOT ALL OF THEM •Bed Basics •Bath Performance •Beyond

   Beyond
10. None

11. http://www.flickr.com/photos/austinevan/3368444745/

12. Set

13. Set require 'set'

14. Set require 'set' s = Set.new([1, 2, 3, 1, 1,

    1]) puts s.inspect # => #<Set: {1, 2, 3}>

15. Enumerable

16. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def

    initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end

17. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def

    initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end files = MyFileChanger.new files << '/etc/profile' << '/etc/bashrc' files.each_with_index do |(name, content), index| puts "#{index}. #{name} is #{content.bytesize} bytes" end names = files.map do |(name, content)| name end puts names.inspect size = files.reduce(0) do |sum, (name, content)| sum + content.bytesize end puts size

18. Enumerable class MyFileChanger include Enumerable File = Struct.new(:name, :content) def

    initialize @files = [] end def <<(filename) content = ::File.read(filename) @files << File.new(filename, content) self end def each @files.each do |file| yield([file.name, file.content]) end end end files = MyFileChanger.new files << '/etc/profile' << '/etc/bashrc' files.each_with_index do |(name, content), index| puts "#{index}. #{name} is #{content.bytesize} bytes" end names = files.map do |(name, content)| name end puts names.inspect size = files.reduce(0) do |sum, (name, content)| sum + content.bytesize end puts size 0. /etc/profile is 189 bytes 1. /etc/bashrc is 745 bytes ["/etc/profile", "/etc/bashrc"] 934

19. Enumerator

20. Enumerator a = [1, 2, 3] a.each { |n| puts

    n } Enumerator.new(a).each { |n| puts n }

21. Enumerator a = [1, 2, 3] a.each { |n| puts

    n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end

22. Enumerator a = [1, 2, 3] a.each { |n| puts

    n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end class Integer def prime? return false if self < 2 max = Math.sqrt(self).floor (2..max).none? { |n| self % n == 0 } end end primes = Enumerator.new do |y| y << 2 odds.each do |n| y << n if n.prime? end end

23. Enumerator a = [1, 2, 3] a.each { |n| puts

    n } Enumerator.new(a).each { |n| puts n } naturals = Enumerator.new do |y| n = 1 loop do y << n n += 1 end end odds = Enumerator.new do |y| naturals.each do |n| y << n if n % 2 != 0 end end class Integer def prime? return false if self < 2 max = Math.sqrt(self).floor (2..max).none? { |n| self % n == 0 } end end primes = Enumerator.new do |y| y << 2 odds.each do |n| y << n if n.prime? end end puts primes.take(10).inspect # => [2, 3, 5, 7, 11, 13, 17, 19, 23, 29]

24. SimpleDelegator

25. SimpleDelegator require 'delegate'

26. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self

    == 'fancy' end end

27. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self

    == 'fancy' end end s = FancyString.new('fancy') puts s.fancy? # => true

28. SimpleDelegator require 'delegate' class FancyString < SimpleDelegator def fancy? self

    == 'fancy' end end s = FancyString.new('fancy') puts s.fancy? # => true puts s.length # => 5

29. Forwardable

30. Forwardable require 'forwardable'

31. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable #

    Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end

32. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable #

    Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!')

33. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable #

    Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!') puts s.fancy_length # => 6 puts s.include?('!') # => true

34. Forwardable require 'forwardable' FancyString = Struct.new(:str) do extend Forwardable #

    Single delegation def_delegator :str, :length, :fancy_length # Multiple delegations def_delegators :str, :include?, :match end s = FancyString.new('Hello!') puts s.fancy_length # => 6 puts s.include?('!') # => true puts s.bytesize # => NoMethodError
35. None

36. Benchmark

37. Benchmark require 'benchmark' results = Benchmark.measure do 1_000_000.times { |i|

    i.to_s } GC.start end puts results # => 0.480000 0.010000 0.490000 ( 0.487643)

38. Benchmark require 'benchmark' results = Benchmark.measure do 1_000_000.times { |i|

    i.to_s } GC.start end puts results # => 0.480000 0.010000 0.490000 ( 0.487643) n = 5000000 # Simple benchmark Benchmark.bm do |x| x.report { for i in 1..n; a = "1"; end } x.report { n.times do ; a = "1"; end } x.report { 1.upto(n) do ; a = "1"; end } end

39. Benchmark

40. Benchmark # Nice reporting labels Benchmark.bm(10) do |x| x.report('for:') {

    for i in 1..n; a = "1"; end } x.report('times:') { n.times do ; a = "1"; end } x.report('upto:') { 1.upto(n) do ; a = "1"; end } end # Warmup Benchmark.bmbm(10) do |x| x.report('for:') { for i in 1..n; a = "1"; end } x.report('times:') { n.times do ; a = "1"; end } x.report('upto:') { 1.upto(n) do ; a = "1"; end } end

41. RubyVM http://timelessrepo.com/tailin-ruby

42. RubyVM def acc(i, n, result) if i == -1 result

    else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end puts fib(10000) # => stack level too deep (SystemStackError) http://timelessrepo.com/tailin-ruby

43. RubyVM::InstructionSequence

44. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false

    }

45. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false

    } RubyVM::InstructionSequence.new(<<-EOF).eval def acc(i, n, result) if i == -1 result else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end EOF

46. RubyVM::InstructionSequence RubyVM::InstructionSequence.compile_option = { :tailcall_optimization => true, :trace_instruction => false

    } RubyVM::InstructionSequence.new(<<-EOF).eval def acc(i, n, result) if i == -1 result else acc(i - 1, n + result, n) end end def fib(i) acc(i, 1, 0) end EOF puts fib(10000) # => A number with 2090 digits

47. Fiddle

48. Fiddle require 'fiddle' include Fiddle

49. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib')

50. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f =

    libm['sqrt']

51. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f =

    libm['sqrt'] args = [TYPE_DOUBLE]

52. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f =

    libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE

53. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f =

    libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE sqrt = Function.new(f, args, ret)

54. Fiddle require 'fiddle' include Fiddle libm = DL.dlopen('/usr/lib/libm.dylib') f =

    libm['sqrt'] args = [TYPE_DOUBLE] ret = TYPE_DOUBLE sqrt = Function.new(f, args, ret) puts sqrt.call(81) # => 9.0

55. WeakRef

56. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml #

    => "<html>..." puts bightml.weakref_alive? # => true

57. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml #

    => "<html>..." puts bightml.weakref_alive? # => true GC.start

58. WeakRef require 'weakref' bightml = WeakRef.new(read_html('http:// bigpage.com/')) puts bightml #

    => "<html>..." puts bightml.weakref_alive? # => true GC.start puts bightml.weakref_alive? # => false

59. http://www.flickr.com/photos/bobcanada/4506301467/

60. SecureRandom

61. SecureRandom require 'securerandom'

62. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg==

63. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex

    # => 9e70e038fc7faf20106c304854c21b8a

64. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex

    # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1"

65. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex

    # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587

66. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex

    # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587 puts SecureRandom.random_number(50) # => 37

67. SecureRandom require 'securerandom' puts SecureRandom.base64 # => 9d4va7k0/XhK2EqYMXJ2jg== puts SecureRandom.hex

    # => 9e70e038fc7faf20106c304854c21b8a puts SecureRandom.random_bytes.inspect # => "r>0\xD1\xA4\x00t&\x82\xFCEl_\x17w\xF1" puts SecureRandom.random_number # => 0.47149176126339587 puts SecureRandom.random_number(50) # => 37 puts SecureRandom.uuid # => 3a34412c-4798-4985-9a43-7d36a6e0d116

68. GServer

69. GServer require 'gserver'

70. GServer require 'gserver' require 'securerandom' class RandomServer < GServer def

    serve(io) cmd = io.read(4).strip case cmd when 'hex' then io.puts(SecureRandom.hex) when 'uuid' then io.puts(SecureRandom.uuid) end end end

71. GServer require 'gserver' require 'securerandom' class RandomServer < GServer def

    serve(io) cmd = io.read(4).strip case cmd when 'hex' then io.puts(SecureRandom.hex) when 'uuid' then io.puts(SecureRandom.uuid) end end end server = RandomServer.new(10101) server.start server.join

72. Kernel#spawn

73. Kernel#spawn def capture(cmd) r, w = IO.pipe pid = spawn(cmd,

    :out => w) w.close Process.wait(pid) r.read ensure r.close end output = capture('randomizer') print output

74. Shellwords

75. Shellwords require 'shellwords'

76. Shellwords require 'shellwords' pattern = '; rm -rf /; '

    capture("randomizer #{pattern.shellescape} /dev/*")

77. Shellwords require 'shellwords' pattern = '; rm -rf /; '

    capture("randomizer #{pattern.shellescape} /dev/*") # Assuming our capture function could take *args like system

78. Shellwords require 'shellwords' pattern = '; rm -rf /; '

    capture("randomizer #{pattern.shellescape} /dev/*") # Assuming our capture function could take *args like system capture('randomizer', pattern, '/dev/*') # => Nope

79. PStore

80. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe

    = true

81. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe

    = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end

82. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe

    = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end

83. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe

    = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end store.transaction do store[:randoms] = [] store.abort # Or an Exception end

84. PStore require 'pstore' store = PStore.new('randomizer', thread_safe = true) store.ultra_safe

    = true store.transaction do store['App'] = 'The Randomizer' store[:randoms] ||= [] store[:randoms] << Randomizer.uuid end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end store.transaction do store[:randoms] = [] store.abort # Or an Exception end store.transaction do puts store[:randoms].inspect # => ["901dcd24-fa10-4194-b25b-8ad49bc875fb"] end

85. I heard you like testing...

86. I heard you like testing...

87. MiniTest

88. MiniTest require 'minitest/autorun' class MathTest < MiniTest::Unit::TestCase def test_addition assert_equal

    2, 1 + 1 end end describe Integer do it 'should subtract' do (1 - 1).must_equal(0) end end

89. MiniTest require 'minitest/autorun' class MathTest < MiniTest::Unit::TestCase def test_addition assert_equal

    2, 1 + 1 end end describe Integer do it 'should subtract' do (1 - 1).must_equal(0) end end describe 'Mocks' do it 'should mock things' do mock = MiniTest::Mock.new mock.expect(:length, 10) mock.length.must_equal(10) mock.verify end end

90. Other Fun Things • OptionParser/optparse, GetoptLong/getoptlong • Two command line

    option parsers! • WEBrick => require ‘webrick’ • Threaded HTTP server. • Rss => require ‘rss’ • Parse and generate RSS feeds. In the stdlib. wat.

91. Other Fun Things • Drb => require ‘drb’ • Distributed

    object system. • Find => require ‘find’ • Recursively iterate the filesystem. • Ripper => require ‘ripper’ • Parse ruby files

92. Other Fun Things • ThreadsWait => require ‘thwait’ • Wait

    for a bunch of threads, block called for each when it finishes. • Queue/SizedQueue => require ‘thread’ • << things in, #pop things out. • MonitorMixin => require ‘monitor’ • Thread safety with synchronize block.

93. Other Fun Things • Net::POP3 => require ‘net/pop’ • Talk

    POP3 email. • Net::IMAP => require ‘net/imap’ • Talk IMAP email. • Net::SMTP => require ‘net/smtp’ • Talk to SMTP servers.

94. Other Fun Things • Net::FTP => require ‘net/ftp’ • Talk

    FTP • Net::HTTP => require ‘net/http’ • Talk HTTP
95. None

96. THANKS!! @darkhelmetlive darkhelmet verboselogging.com GetYardstick.com https://www.makesets.com/the-ruby-standard-library