ruby 1.9

Ruby 1.9: It [email protected]

2009/4/18OSDC.TW

2009年4月19日星期日

mailto:[email protected]






Ruby 1.9: It [email protected]

2009/4/18OSDC.TW

(must)








我是誰?• 張文鈿 a.k.a. ihower

• http://ihower.idv.tw/blog/

• http://twitter.com/ihower

• 從 2006 年開始使用 Ruby

• 和多(股)公司 Rails Developer

• http://handlino.com

• http://registrano.com


http://ihower.idv.tw/blog/




http://handlino.com

http://handlino.com

http://registrano.com

http://registrano.com

Agenda

• Overview

• What’s changed?

• What’s New? (External Interater, M17N, The Threading Model)

• Ruby 1.9 on Rails


1. Overview


Ruby 1.8.6廣為使用的版本

• Ruby 1.8.6, release at 2007/3/12

• Stable

• Performance sucks

• Memory leaks

• NewRelic Report 69.4% 使用率http://railslab.newrelic.com/2009/04/01/the-state-of-the-stack-a-ruby-on-rails-benchmarking-report


http://railslab.newrelic.com/2009/04/01/the-state-of-the-stack-a-ruby-on-rails-benchmarking-report

http://railslab.newrelic.com/2009/04/01/the-state-of-the-stack-a-ruby-on-rails-benchmarking-report

Ruby 1.8.7敬而遠之的版本

• Ruby 1.8.7 release at 2008/5/31

• 移植了部份 1.9 的功能

• gems, library 相容性變差 (與1.8.6不完全相容)

• JRuby 跳過 1.8.7 不實做

• NewRelic Report 14.5% 使用率


Ruby 1.9尚待推廣的版本

• Ruby 1.9.0 release development version in 2007/12/25

• Ruby 1.9.1 release stable/production version in 2009/1/30

• Better performance

• Better encoding support


Ruby Implementations能上 production 的

• Ruby 1.8.6, 1.8.7 (MRI, Matz’ Ruby Interpreter)

• EngineYard 將接手維護 1.8.6，預計將帶入 MBARI 的 GC patch

• Ruby 1.9.1 (YARV)

• JRuby

• 相容 Ruby1.8.6 語法，最新版涵蓋 1.9 功能。

• Ruby Enterprise Edition(REE)

• 衍生自 Ruby 1.8.6，但是大修 GC，改善 memory leak 問題

http://www.infoq.com/news/2009/01/ruby-patches-fix-leaks




Ruby Implementations還不能上 production 的

• MacRuby (based on Objective-C)

• Rubinius (Engine yard project)

• MagLev (based on smalltalk)

• IronRuby (based on Microsoft .NET)

• Cardinal (based on Parrot VM)


Performance (平均比 1.8 快 2~2.5 倍)

http://antoniocangiano.com/category/ruby-benchmark-suite/http://github.com/acangiano/ruby-benchmark-suite/


http://antoniocangiano.com/category/ruby-benchmark-suite/

http://antoniocangiano.com/category/ruby-benchmark-suite/

http://github.com/acangiano/ruby-benchmark-suite/tree/master

http://github.com/acangiano/ruby-benchmark-suite/tree/master

Ubuntu : Intel® Q6600® quad-coreComputer Language Benchmarks Game

http://shootout.alioth.debian.org/


http://shootout.alioth.debian.org/u32q/index.php




http://shootout.alioth.debian.org

http://shootout.alioth.debian.org

2. What’s changed?


Ordered Hash會照順序排

{:a=>1, :d=>4, :b=>2, :c=>3}1.8

1.9

{ :a => 1, :b=> 2, :c => 3 }.merge( :d => 4 )

{:a=>1, :b=>2, :c=>3, :d=>4}


new Hash literal新的雜湊語法

config = { :foo => 1234, :bar => 6789 }

config = { foo: 1234, bar: 6789 }

1.8,1.9

1.9

Person.find(:all, :conditions => { :name => 'ihower' } )

Person.find(:all, :conditions => { name: 'ihower' } )


Hash syntax不允許用逗號取代 =>

1.8 {1,2,3,4}=> {1=>2, 3=>4}

{1,2,3,4}=> syntax error, unexpected ',', expecting tASSOC1.9


Hash#selecthash = { :a => 1, :b => 2, :c => 3 }hash.select{ |k, v| v > 1 }

[[:b, 2], [:c, 3]]

{:b=>2, :c=>3}

1.8

1.9


Array#to_s, Hash#to_s

[1,2,3,4].to_s => "1234" {1=>2,3=>4}.to_s => "1234"

[1,2,3,4].to_s => "[1, 2, 3, 4]" {1=>2,3=>4}.to_s => "{1=>2, 3=>4}"

1.91.8


case syntax移除冒號用法

name = case when x == 1 : "one" when x == 2 : "two" else "many" end

name = case when x == 1 then "one" when x == 2 then "two" else "many" end

name = case when x == 1 "one" when x == 2 "two" else "many" end

1.8 1.8,1.9

1.8,1.9


block’s parameter always local區塊參數必是 local 變數

x = "foo"y = "bar"

[1,2,3].each do |x| y=x+1end

1.9[x,y] => [3, 4] [x,y] => ["foo", 4]1.8


block’s parameter always local區塊參數必是 local 變數

x = "foo"y = "bar"

[1,2,3].each do |x| y=x+1end

1.9[x,y] => [3, 4] [x,y] => ["foo", 4]1.8

造成必須小心命名避免蓋掉外面的變數


block-local variable明確宣告區塊內的變數是 local

bar = "ihower"

[1,2,3].each do |val| foo = val bar = val end

foo # NameError: undefined local variable or method `foo’bar => 3

bar = "ihower"

[1,2,3].each do |val; bar| bar = valend

bar => "ihower"

1.91.8,1.9


block-local variable明確宣告區塊內的變數是 local

bar = "ihower"

[1,2,3].each do |val| foo = val bar = val end

foo # NameError: undefined local variable or method `foo’bar => 3

bar = "ihower"

[1,2,3].each do |val; bar| bar = valend

bar => "ihower"

1.91.8,1.9

可避免 bar 變數被蓋掉


block can accept block argrments區塊參數列亦可使用區塊變數

proc1 = lambda do |a, *b, &block| p a p b p c block.callend

proc1.call(1,2,3,4) { puts "in block1" }

# 輸出1[2,3,4]"in block1"


new lambda literal新的 lambda 語法

->(a) { a*3 }.(4)# => 12

lambda { |a| a*3 }.call(4)# => 12

lambda { |a| a*3 }[4]# => 12

1.8,1.9

1.8,1.9

1.9


def my_if(condition, then_clause, else_clause) if condition then_clause.call else else_clause.call endend

5.times do |val| my_if (val < 3), -> { puts "#{val} is small" }, -> { puts "#{val} is big" }end

# 輸出0 is small1 is small2 is small3 is big4 is big


def my_while(cond, &body) while cond.call body.call endend

a = 0my_while -> { a < 3 } do puts a a += 1end

# 輸出012


Kernel.proc大地雷, do not use it!

• proc 等同於 lambda

• proc 修正成 Proc.new1.9

1.8


BasicObject新的繼承體系 root

Class.superclass.superclass.superclass => nil

Class.superclass.superclass.superclass => BasicObjectBasicObject.superclass => nil1.9

Class.superclass.superclass => Object

BasicObject.instance_methods=> [:==, :equal?, :!, :!=, :instance_eval, :instance_exec, :__send__]

1.8

1.8,1.9

可用在 metaprogramming 時的 blank canvas


standard library changes• + Rubygems

• no longer needed require ‘rubygems’

• + Rake

• no longer gem install rake

• ~ Test::Unit replaced by MiniTest

• - soap, jcode...etc, some rarely used, old libraries


3. What’s new?


External Iterator


Iterators建立外部迭代子 to_enum

arr = [ 1, 2, "ihower" ]enum_a = arr.to_enum # 建立 Enumerators 物件 (預設用each)

enum_a.next # => 1enum_a.next # => 2enum_a.next # => "ihower"

ExternalInternalarr = [ 1, 2, "ihower" ]arr.each do |a| puts a end

# => 1# => 2# => "ihower"

1.91.8,1.9


Enumerators更多範例

h = { foo: "567", bar: "890" }enum_h = h.to_enumenum_h.next # => [:foo, "567"]enum_h.next # => [:bar, "890"]

arr = [ 1, 2, "ihower" ]enum_a = arr.to_enum(:each_with_index)

enum_a.next # => [1, 0]enum_a.next # => [2, 1]enum_a.next # => ["ihower", 2]

1.9 1.9


StopIteration exception同時迭代數個物件

short_enum = [1, 2, 3].to_enumlong_enum = ('a'..'z').to_enum

loop do puts "#{short_enum.next} #{long_enum.next}"end

# => 1-a# => 2-b# => 3-c

1.9


StopIteration exception同時迭代數個物件

short_enum = [1, 2, 3].to_enumlong_enum = ('a'..'z').to_enum

loop do puts "#{short_enum.next} #{long_enum.next}"end

# => 1-a# => 2-b# => 3-c

用完時丟出 StopIteration 例外

1.9


Enumerator from iterator亦可從 iterator method 建立

arr = [ 1, 2, "ihower" ]enum_a = arr.each # 使用迭代子函式來建立 Enumerator 物件

enum_a.next # => 1enum_a.next # => 2enum_a.next # => "ihower"

1.9


Enumerators.new使用 code block 手動建立

seq = Enumerator.new do |yielder| n1 = 0 n2 = 1 loop do n3 = n1 + n2 yielder.yield n3 n1 = n2 n2 = n3 endend

seq.next # 1seq.next # 22.times { puts seq.next }# 3# 5

無窮迴圈

回傳值並在此暫停

1.9


Enumerator objects are also enumerable

seq.first(10)# => [1, 2, 3, 5, 8, 13, 21, 34, 55, 89]

seq.to_a# Don’t do this if your Enumerator has infinite elements

1.9


M17N(Multilingualization)


In Ruby 1.8, a String is always just a collection of bytes


Ruby 1.8 String fails>> "中文".reverse=> "\207\226歸\344"

>> "中文".size=> 6

1.8


Ruby 1.8 Regexp有支援 UTF-8

• Support None (n or N), EUC (e or E), Shift_JIS (s or S), UTF-8 (u or U)

>> "中文".scan(/./u)=> ["中", "文"]

1.8,1.9


Use Regexp to handle String使用 Regexp 拯救字串處理

>> "中文".scan(/./u).reverse.join=> "文中"

>> "中文".scan(/./u).size=> 2

1.8,1.9


$KCODE = “U”or ruby -KU

• 變更 regular expressions 的 default encoding

• $KCODE = "U" 也可以讓 terminal 正確顯示

>> "中文"=> "\344\270\255\346\226\207">> $KCODE='u'>> "中文"=> "中文"

1.8


Unicode codepoint另一種在 Ruby 1.8 拯救 UTF-8 字串的方式

>> "中文".unpack("U*")=> [20013, 25991]

>> "中文".unpack("U*").reverse.pack("U*")=> "文中"

>> "中文".unpack("U*").size=> 2

1.8,1.9


Unicode codepoint(cont.)Rails ActiveSupport 使用這個技巧

>> "中文".chars # in Rails=> #<ActiveSupport::Multibyte::Chars:0x25aebbc @wrapped_string="中文">

>> "中文".chars.size => 2

1.8,1.9


iconv library處理非 UTF-8 data

• C Library, it’s fast.

• convert your encoding to UTF-8

• handle it

• export back to your encoding


jcode librarytoo simple, not useful

1.8 $KCODE = 'UTF8'require 'jcode'

str = "中文"str.size # 9str.jsize # 2


No enough encodings supported in Ruby 1.8

• String 沒有 Encoding 機制

• Regexp 支援不夠全面

• 一直加 encoding 支援並不是辦法，總會用完 Regexp letter

• 也不能簡單解決其他問題，例如處理 #String.upcase、encoded data 是否 valid?

• $KCODE 是全域變數

• String, IO object, program source 可能都不同


pick one encoding, likely Unicode, and works all data in one format? No.

Ruby 1.9 make it possible to work with data with 83 encoding.


>> Encoding.name_list

=> ["ASCII-8BIT", "UTF-8", "US-ASCII", "Big5", "CP949", "Emacs-Mule", "EUC-JP", "EUC-KR", "EUC-TW", "GB18030", "GBK", "ISO-8859-1", "ISO-8859-2", "ISO-8859-3", "ISO-8859-4", "ISO-8859-5", "ISO-8859-6", "ISO-8859-7", "ISO-8859-8", "ISO-8859-9", "ISO-8859-10", "ISO-8859-11", "ISO-8859-13", "ISO-8859-14", "ISO-8859-15", "ISO-8859-16", "KOI8-R", "KOI8-U", "Shift_JIS", "UTF-16BE", "UTF-16LE", "UTF-32BE", "UTF-32LE", "Windows-1251", "BINARY", "IBM437", "CP437", "IBM737", "CP737", "IBM775", "CP775", "CP850", "IBM850", "IBM852", "CP852", "IBM855", "CP855", "IBM857", "CP857", "IBM860", "CP860", "IBM861", "CP861", "IBM862", "CP862", "IBM863", "CP863", "IBM864", "CP864", "IBM865", "CP865", "IBM866", "CP866", "IBM869", "CP869", "Windows-1258", "CP1258", "GB1988", "macCentEuro", "macCroatian", "macCyrillic", "macGreek", "macIceland", "macRoman", "macRomania", "macThai", "macTurkish", "macUkraine", "CP950", "stateless-ISO-2022-JP", "eucJP", "eucJP-ms", "euc-jp-ms", "CP51932", "eucKR", "eucTW", "GB2312", "EUC-CN", "eucCN", "GB12345", "CP936", "ISO-2022-JP", "ISO2022-JP", "ISO-2022-JP-2", "ISO2022-JP2", "ISO8859-1", "Windows-1252", "CP1252", "ISO8859-2", "Windows-1250", "CP1250", "ISO8859-3", "ISO8859-4", "ISO8859-5", "ISO8859-6", "Windows-1256", "CP1256", "ISO8859-7", "Windows-1253", "CP1253", "ISO8859-8", "Windows-1255", "CP1255", "ISO8859-9", "Windows-1254", "CP1254", "ISO8859-10", "ISO8859-11", "TIS-620", "Windows-874", "CP874", "ISO8859-13", "Windows-1257", "CP1257", "ISO8859-14", "ISO8859-15", "ISO8859-16", "CP878", "SJIS", "Windows-31J", "CP932", "csWindows31J", "MacJapanese", "MacJapan", "ASCII", "ANSI_X3.4-1968", "646", "UTF-7", "CP65000", "CP65001", "UTF8-MAC", "UTF-8-MAC", "UCS-2BE", "UCS-4BE", "UCS-4LE", "CP1251", "locale", "external", "internal"]


All String are Encoded• In Ruby 1.9 a String is a collection of

encoded characters.除了 raw bytes，還包括 Encoding 資訊。

>> "中文".encoding.name=> "UTF-8"1.9

Encoding object


String works in characters

>> "中文".reverse=> "文中"

>> "中文".size=> 2

>> "中文".bytesize=> 6

1.9


String Indexing

>> "abc"[0]=> 97

>> "中文"[1]=> 184

>> "abc"[0]=> "a"

>> "中文"[1]=> "文"

1.91.8

>> "abc"[0].ord=> 97


萬歲!

In Ruby 1.9, String has attached Encoding object, and works in

characters.


Transcoding改變編碼

utf8 = "測試"utf8.bytesize # 6utf8.bytes.to_a # [230, 184, 172, 232, 169, 166]

big5 = utf8.encode("big5")

big5.encoding.name # ”Big5”big5.bytesize # 4big5.bytes.to_a # [180, 250, 184, 213]

1.9


Transcoding fails轉碼失敗

str = "Résumé"str.encode("big5")

=> Encoding::UndefinedConversionError: "\xC3\xA9" from UTF-8 to Big5 from (irb):2:in `encode' from (irb):2 from /usr/local/bin/irb19:12:in `<main>'

1.9


Force Transcoding改變編碼，但不改 byte data

utf8 = "測試"

big5 = utf8.encode("big5")big5.valid_encoding?=> true

big5.force_encoding("utf-8")big5.valid_encoding?=> false

1.9


Force Transcoding fails編碼不對無法進一步操作

big5.valid_encoding? # falsebig5 =~ /123456/

=> ArgumentError: invalid byte sequence in UTF-8 from (irb):11 from /usr/local/bin/irb19:12:in `<main>'

1.9


Encoding.compatible?例如: ASCII with a bigger Encoding

ascii = "my ".force_encoding("ascii")utf8 = "Résumé"

# 檢查相容性Encoding.compatible?(ascii, utf8) #<Encoding:UTF-8>

# 相加my_resume = ascii + utf8puts my_resume # "My Résumé"puts my_resume.encoding.name # UTF-8

1.9


Encoding.compatible?不相容不能加在一起

big5 = "測試".encode("big5")utf8 = "Résumé"

# 檢查相容性Encoding.compatible?(big5, utf8) # nil

# 相加big5 + utf8

=> Encoding::CompatibilityError: incompatible character encodings: Big5 and UTF-8 from (irb):25 from /usr/local/bin/irb19:12:in `<main>'

1.9


String Iterationeach 被移除了

• Strings are no longer enumerable

• Ruby 1.8 each() has been removed

• Ruby 1.9 use explicit iterator

• each_line

• each_byte

• each_char

• each_codepoint

1.9


疑? 那預設的 encoding 是什麼?

What’s default encoding?


program source encoding放在檔案開頭的 magic comment

# encoding: UTF-8或

#!/usr/bin/env ruby -w# encoding: UTF-8或

# coding: UTF-8或

# -*- coding: UTF-8 -*-


program without magic comment如果沒有指定編碼

ruby foobar.rb # US-ASCII

ruby -e foobar.rb 或用 irb # 會看 OS 的語系設定 ($LC_CTYPE, $LANG)

ruby -KU foobar.rb # UTF-8，與 Ruby 1.8 相容的指令


invalid multibyte char (US-ASCII)

如果程式碼中有不符合 program source encoding 的字元，程式執行會 error


IO Object讀檔案

# encoding: utf-8f = File.open("big5.txt","r:big5")puts f.external_encoding # Big5puts f.gets.encoding # Big5

1.9 這是一個大五碼檔案


IO Object讀檔案並自動轉碼

# encoding: utf-8f = File.open("big5.txt","r:big5:utf-8")puts f.external_encoding # Big5puts f.internal_encoding # UTF-8puts f.gets.encoding # UTF-8

1.9


IO Object寫檔案

1.9# encoding: utf-8f = File.open("another_big5.txt", "w:big5")puts f.external_encoding # Big5data = "中文字"puts data.encoding.name # UTF-8f << data


IO Object寫檔案

1.9# encoding: utf-8f = File.open("another_big5.txt", "w:big5")puts f.external_encoding # Big5data = "中文字"puts data.encoding.name # UTF-8f << data

寫入大五碼


Regexp has encoding too

• Oniguruma enginehttp://www.geocities.jp/kosako3/oniguruma/

• Same basic API

• better performance

• support for a lot of encoding

• extended syntax

/\w/.encoding=> #<Encoding:US-ASCII>

/中文/.encoding=> #<Encoding:UTF-8>

1.9


http://www.geocities.jp/kosako3/oniguruma/

http://www.geocities.jp/kosako3/oniguruma/

Default Encoding Overview

• String literal 按照 program source 編碼

• Symbols 和 Regexp 如果只有用到 7-bit，會是 US-ASCII，不然則按照 program source 編碼。

• IO 物件的 external_encoding 按照 OS 語系設定

• 或使用 ruby -E 指定編碼

• 或設定 Encoding.external_encoding


The Threading model


Fibers 協同常式(semi-coroutine)

一種可以多次進出 code block 的控制結構


f = Fiber.new { 2.times do puts "Fiber say hi" Fiber.yield # 將控制權轉回呼叫者 puts "Fiber say bye" end} # 不會立即執行

>> f.resume# 輸出 Fiber say hi>> f.resume# 輸出 Fiber say bye# 輸出 Fiber say hi>> f.resume# 輸出 Fiber say bye>> f.resume FiberError: dead fiber called from (irb):78:in `resume' from (irb):78 from /usr/local/bin/irb19:12:in `<main>'

1.9


Fibers 用途• 實做 Enumerator 外部迭代子

• 擴充 fiber library 可以將控制權轉給別的 fiber object

• 取代難以實做的 continuation 機制(Ruby 1.8 的 continuation 從 kernel 移到 library)

• 日常生活應該用不到... zzz


Native Threads

• Green threads所有 Ruby thread 共用一個 native thread

• Native (operation system) thread 每個 Ruby thread 配一個 native thread

1.9

1.8


GILGiant Interpreter Lock

• 由於部份 C extension libraries 並不 thread safe，所以實作上同一時間只會有一個 Thread 在執行。(據說將來會解鎖，所以目前最好的 Ruby Threads 實做應該是 JRuby)

1.9


4. Ruby on Rails


Ruby 1.9 on Rails

• Rails 2.3.2 or edge

• mysql-ruby driver for Ruby 1.9

• Passenger(mod_rails) or Thin


Upgrade issue哪裡會爆炸

• program source encoding problem

• invalid multibyte char 如果有中文在原始碼中，一定要加 # encoding: UTF-8

• encoding compatibility problem

• 資料庫撈出來的資料被認為是 ACSII-8BIT (binary)，無法與 UTF-8 String 相加

• http://github.com/hectoregm/mysql-ruby (UTF-8 friendly)

• some gem, plugins are not Ruby 1.9 compatible

• http://isitruby19.com/


http://github.com/hectoregm/mysql-ruby

http://github.com/hectoregm/mysql-ruby

http://isitruby19.com

http://isitruby19.com

Benchmark我的實驗

• Rails 2.3.2 production mode

• No DB, just render :text => 'hello'

• My MacBook Pro 2.2G

• httperf


PerformanceReply rate [replies/s]

min avg max stddev

Ruby 1.8.6Mongrel

1.1.5

241.8 258.3 267.4 14.4

Ruby 1.8.6mod_rails

244.6 260.9 271.2 11.4

Ruby 1.9.1mod_rails

264.0 269.5 273.4 4.9

Ruby 1.8.6Thin 1.0.0

244.5 273.2 299.6 22.7

Ruby 1.9.1Thin 1.0.0

348.4 363.2 371.2 12.8


PerformanceRuby 1.9 快兩倍，不表示 Rails Stack 也可以快兩倍!!

0

100

200

300

400

Reply rate [replies/s]

Ruby 1.8.6/Mongrel 1.1.5Ruby 1.8.6/mod_rails edgeRuby 1.9.1/mod_rails edgeRuby 1.8.6/Thin 1.0.0Ruby 1.9.1/Thin 1.0.0


PerformanceRuby 1.9 快兩倍，不表示 Rails Stack 也可以快兩倍!!

0

100

200

300

400

Reply rate [replies/s]

Ruby 1.8.6/Mongrel 1.1.5Ruby 1.8.6/mod_rails edgeRuby 1.9.1/mod_rails edgeRuby 1.8.6/Thin 1.0.0Ruby 1.9.1/Thin 1.0.0

果然天底下沒這麼好的事


5. Conclusion結論


TIOBE Programming Community Index for April 2009


Ruby challenge

• Ruby 1.9 change a lot and 1.8 is slow and should be deprecated.

• Migrate to Ruby 1.9 is the big challenge in 2009.


Reference• Understanding M17n

http://blog.grayproductions.net/articles/understanding_m17n

• Books

• Programming Ruby 1.9 (Pragmatic)

• The Ruby Programming Language (O’Reilly)

• Ruby Best Practices (O’Reilly)

• The Well-Grounded Rubyist (Manning)

• Slide

• MigrationToRuby 1.9

• Ruby 1.9: What to Expect http://slideshow.rubyforge.org/ruby19.html

• Matz on Ruby 1.9




http://slideshow.rubyforge.org/ruby19.html

http://slideshow.rubyforge.org/ruby19.html

Other reference links

• http://svn.ruby-lang.org/repos/ruby/tags/v1_9_1_0/NEWS

• http://blog.nuclearsquid.com/writings/ruby-1-9-what-s-new-what-s-changed

• http://blog.grayproductions.net/articles/getting_code_ready_for_ruby_19

• http://dablog.rubypal.com/2009/1/14/10-things-to-be-aware-of-in-moving-to-ruby-1-9

• http://dablog.rubypal.com/2009/1/16/son-of-10-things-to-be-aware-of-in-ruby-1-9

• http://blog.kineticweb.com/articles/2009/01/30/ruby-1-9-1-the-other-features


http://svn.ruby-lang.org/repos/ruby/tags/v1_9_1_0/NEWS

http://svn.ruby-lang.org/repos/ruby/tags/v1_9_1_0/NEWS

http://blog.nuclearsquid.com/writings/ruby-1-9-what-s-new-what-s-changed

http://blog.nuclearsquid.com/writings/ruby-1-9-what-s-new-what-s-changed

http://blog.grayproductions.net/articles/getting_code_ready_for_ruby_19

http://blog.grayproductions.net/articles/getting_code_ready_for_ruby_19

http://dablog.rubypal.com/2009/1/14/10-things-to-be-aware-of-in-moving-to-ruby-1-9




http://dablog.rubypal.com/2009/1/16/son-of-10-things-to-be-aware-of-in-ruby-1-9




Thank you.


Bonus


Object#tap串接用

puts "dog".reverse.tap{ |o| puts "reversed: #{o}" }.upcase

# 輸出reversed: godGOD

回傳原物件


ruby 1.9

Documents

undefined local variable

method foobar

local local

8f file

6 mod rails edgeruby 1

92009419stopiteration exceptionshort enum

1 mod rails edgeruby 1

external encoding big5puts