{:web=>:wxianfeng}

>/usr/bin/ruby -e "$(curl -fsSL https://raw.github.com/gist/323731)"

>brew install imagemagick

curl: (7) couldn't connect to host
Error: Failure while executing: /usr/bin/curl -f#LA Homebrew\ 0.8\ (Ruby\ 1.8.7-249;\ Mac\ OS\ X\ 10.7.1) ftp://ftp.remotesensing.org/pub/libtiff/tiff-3.9.5.zip -o /Users/wangxianfeng/Library/Caches/Homebrew/libtiff-3.9.5.zip

>/usr/bin/curl http://download2.osgeo.org/libtiff/tiff-3.9.5.zip -o ~/Library/Caches/Homebrew/libtiff-3.9.5.zip

>brew install imagemagick

wxianfeng:inono wangxianfeng$ convert --version
Version: ImageMagick 6.7.1-1 2011-09-10 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2011 ImageMagick Studio LLC
Features: OpenMP

wxianfeng:inono wangxianfeng$ brew list
imagemagick jasper jpeg libtiff little-cms

# Read about fixtures at http://ar.rubyonrails.org/classes/Fixtures.html

one:
  name: MyString
  orgunit_id: 1
  inheritable: false
 # codes 是yaml数组表示方法
 # 缩进只能是两个空格为一级，不能是其他字符
  codes: 
    - 1
    - a
    - 2
    - b
    - 3
    - c

ruby-1.9.2-p0 >   file =  "#{Rails.root}/test/fixtures/enumerations.yml"
 => "/usr/local/system/projects/entos/ent_os/test/fixtures/enumerations.yml" 
ruby-1.9.2-p0 > YAML.load File.read(file) 
 => {"one"=>{"name"=>"MyString", "orgunit_id"=>1, "inheritable"=>false, "codes"=>[1, "a", 2, "b", 3, "c"]}} 

irb(main):001:0> 
=> {"one"=>{"name"=>"MyString", "inheritable"=>false, "orgunit_id"=>1, "codes"=>[1, "a", 2, "b", 3, "c"]}}
irb(main):002:0> require "yaml"
=> true
irb(main):003:0> hsh.to_yaml
=> "--- \none: \n  name: MyString\n  inheritable: false\n  orgunit_id: 1\n  codes: \n  - 1\n  - a\n  - 2\n  - b\n  - 3\n  - c\n"

ruby-1.9.2-p0 > y hsh
--- 
one: 
  name: MyString
  orgunit_id: 1
  inheritable: false
  codes: 
  - 1
  - a
  - 2
  - b
  - 3
  - c
 => nil 

task :test => :environment do 
end

wxianfeng@ubuntu:/usr/local/system/projects/entos/ent_os$ rake environment --trace 
(in /usr/local/system/projects/entos/ent_os)
** Invoke environment (first_time)
** Execute environment

# Add your own tasks in files placed in lib/tasks ending in .rake,
# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.

require File.expand_path('../config/application', __FILE__)
require 'rake'

EntOs::Application.load_tasks

   def initialize_tasks

      require "rails/tasks"

      task :environment do

        $rails_rake_task = true

        require_environment!

      end

    end

namespace :test do
end

task :default => ["test"]

task :test => [:hello,:world]

rake -T  
rake --tasks
rake -T db: # 查看db打头的task

rake test --trace 

wxianfeng@ubuntu:/usr/local/system/projects/entos/ent_os$ rake -h
rake [-f rakefile] {options} targets...

Options are ...
    -C, --classic-namespace          Put Task and FileTask in the top level namespace
    -D, --describe [PATTERN]         Describe the tasks (matching optional PATTERN), then exit.
    -n, --dry-run                    Do a dry run without executing actions.
    -e, --execute CODE               Execute some Ruby code and exit.
    -p, --execute-print CODE         Execute some Ruby code, print the result, then exit.
    -E, --execute-continue CODE      Execute some Ruby code, then continue with normal task processing.
    -I, --libdir LIBDIR              Include LIBDIR in the search path for required modules.
    -P, --prereqs                    Display the tasks and dependencies, then exit.
    -q, --quiet                      Do not log messages to standard output.
    -f, --rakefile [FILE]            Use FILE as the rakefile.
    -R, --rakelibdir RAKELIBDIR,     Auto-import any .rake files in RAKELIBDIR. (default is 'rakelib')
        --rakelib
    -r, --require MODULE             Require MODULE before executing rakefile.
        --rules                      Trace the rules resolution.
    -N, --no-search, --nosearch      Do not search parent directories for the Rakefile.
    -s, --silent                     Like --quiet, but also suppresses the 'in directory' announcement.
    -g, --system                     Using system wide (global) rakefiles (usually '~/.rake/*.rake').
    -G, --no-system, --nosystem      Use standard project Rakefile search paths, ignore system wide rakefiles.
    -T, --tasks [PATTERN]            Display the tasks (matching optional PATTERN) with descriptions, then exit.
    -t, --trace                      Turn on invoke/execute tracing, enable full backtrace.
    -v, --verbose                    Log message to standard output.
    -V, --version                    Display the program version.
    -h, -H, --help                   Display this help message.

wxianfeng@ubuntu:~/test/rake$ cat Rakefile 
desc "Default: test"
task :default => ["r:test"]

namespace :r do 
desc "test" 
task :test  do
        puts "test"
end

desc "test1"
task :test1 => :test do
        puts "test1" 
end

desc "test3"
task :test3 => :test4 do
        puts "test3" 
end 
end

Object#returning has been deprecated in favor of Object#tap

require "rubygems"
require "active_support"
# Object#tap 是>ruby1.8.7 有的
# Object#returning 是Rails 封装的方法, rails3.X 已经不建议使用

# Object#tap 可以支持链式(chain)操作
(1..10).tap {
  |x| puts "original: #{x.inspect}"
}.to_a.tap {
  |x| puts "array: #{x.inspect}"
}.select {|x| x%2==0}.tap {
  |x| puts "evens: #{x.inspect}"
}.map {|x| x*x}.tap {
  |x| puts "squares: #{x.inspect}"
}

def object_tap
  {}.tap do |h| # => Hash.new.tap
    h[:a] = 1
    h[:b] =2
  end
end

p object_tap # {:b=>2, :a=>1}

def object_returning
  returning Hash.new do |h| # 注意这里不能用 {}  , 放在 returning 方法后面 当作成 block闭包了
    h[:a] = 1
    h[:b] = 2
  end  
end

p object_returning # {:b=>2, :a=>1}

require "rubygems"
require "active_support"

class Hash  
  def shift_value_tap_self
    self.tap do |h|
      h.each { |k,v| v.shift if v.is_a?(Array) }
    end
  end
  def shift_value_tap
    {}.tap do |h|
      self.each { |k,v|  v.is_a?(Array) ? h[k] = v.shift : h[k] = v } 
    end
  end

  def shift_value_returning
    returning Hash.new do |h|
      self.each { |k,v|  v.is_a?(Array) ? h[k] = v.shift : h[k] = v } 
    end
  end
  def shift_value_returning_self
    returning self do |h|
      h.each { |k,v| v.shift if v.is_a?(Array) }
    end
  end
end

hsh = {"a"=>[1,2,3],"b"=>["g","f","w"],"c"=>"fuck_china"}
hsh1 = {"a"=>[1,2,3],"b"=>["g","f","w"],"c"=>"fuck_china"}
hsh2 = {"a"=>[1,2,3],"b"=>["g","f","w"],"c"=>"fuck_china"}
hsh3 = {"a"=>[1,2,3],"b"=>["g","f","w"],"c"=>"fuck_china"}
p hsh.shift_value_tap # {"a"=>1, "b"=>"g", "c"=>"fuck_china"}
p hsh1.shift_value_returning # {"a"=>1, "b"=>"g", "c"=>"fuck_china"}
p hsh2.shift_value_tap_self # {"a"=>[2, 3], "b"=>["f", "w"], "c"=>"fuck_china"}
p hsh3.shift_value_returning_self # {"a"=>[2, 3], "b"=>["f", "w"], "c"=>"fuck_china"}

Kernel.const_get(:User) # Object.const_get(:User)
eval(’User’)
‘User’.constantize

Object.const_get(:User) # uninitialized constant User (NameError)

require "rails/all"

def Kernel.const_missing(name)
  Object.const_set(name,Class.new)
end
#p Kernel.const_get("baoxiaos".to_sym) # wrong constant name baoxiaos (NameError)
p Kernel.const_get("baoxiaos".classify.to_sym) # Baoxiao , const的首字母必须大写
p Kernel.constants # []
p Object.constants.include?(:UBaoxiao) # true

require "rails/all"

def Object.const_missing(name)
  Object.const_set(name,Class.new)
end

#p Object.const_get("baoxiaos".to_sym) # wrong constant name baoxiaos (NameError)
p Object.const_get("baoxiaos".classify.to_sym)

  Object.const_set(name,Class.new)

class Object
include Kernel
end

class Foo

  attr_accessor :sex,:birthday  

end

p Foo.new.instance_variables # => []

# ruby version : 1.9.2

class Foo

  attr_accessor :sex,:birthday # attr_accessor ruby里封装的method  

end

p Foo.new.instance_variables # => []

f = Foo.new
p f.sex #=> nil
f.sex = 'M' 
p f.instance_variables #=>  [:@sex]
p f.inspect # => "#<Foo:0x85ead8c @sex=\"M\">"

b = Foo.new
b.birthday = nil # 注意赋值为nil,也开辟了内存空间
p b.instance_variables # => [:@birthday]
p b.inspect # => "#<Foo:0x9dca358 @birthday=nil>"

class Foo
  
  def initialize
    @name = 'wxianfeng'
  end

  def bar # => as getter method
    @name
  end

end

f = Foo.new
p f.instance_variables #=> [:@name]
p f.inspect #=> "#<Foo:0x8aa7c08 @name=\"wxianfeng\">"
p f.name # =>  undefined method `name' for #<Foo:0x99adf7c @name="wxianfeng">
p f.bar # => "wxianfeng"

"ab12cd12".gsub(/(\d+)cd(\1)/,"")   # => "ab"

这个正则就相当于 /(\d+)cd12/  ,因为 \1 引用的是 前面的 (\d+) ,而前面的 (\d+) 匹配出来的结果是  12

"ab12cd".gsub(/(\d+)/,'34\1')  #  => "ab3412cd"

p "ab12cd".gsub(/(\d+)/,'34\1') # "ab3412cd"
p $1  # "12"
p "ab56cd".gsub(/(\d+)/,"78#{$1}") # "ab7812cd" , 这个时候的 $1 为 上面的 12

p "ab12cd".gsub(/(\d+)/,'34\1') # "ab3412cd"
p $1  # "12"
str = "ab56cd".gsub(/(\d+)/) do |ele|
  "78#{$1}" # 这里的 $1 是 56
end
p str # "ab7856cd"

p "ab56cd".gsub(/(\d+)/,"78#{$1}") # "ab78cd" 这里的 $1 是 nil

str = "ab56cd".gsub(/(\d+)/) do |ele|
  "78#{$1}"
end

p str # "ab7856cd"

#     str.gsub(pattern, replacement)       => new_str
  #     str.gsub(pattern) {|match| block }   => new_str
  #
  #
  # Returns a copy of <i>str</i> with <em>all</em> occurrences of <i>pattern</i>
  # replaced with either <i>replacement</i> or the value of the block. The
  # <i>pattern</i> will typically be a <code>Regexp</code>; if it is a
  # <code>String</code> then no regular expression metacharacters will be
  # interpreted (that is <code>/\d/</code> will match a digit, but
  # <code>'\d'</code> will match a backslash followed by a 'd').
  #
  # If a string is used as the replacement, special variables from the match
  # (such as <code>$&</code> and <code>$1</code>) cannot be substituted into it,
  # as substitution into the string occurs before the pattern match
  # starts. However, the sequences <code>\1</code>, <code>\2</code>, and so on
  # may be used to interpolate successive groups in the match.
  #
  # In the block form, the current match string is passed in as a parameter, and
  # variables such as <code>$1</code>, <code>$2</code>, <code>$`</code>,
  # <code>$&</code>, and <code>$'</code> will be set appropriately. The value
  # returned by the block will be substituted for the match on each call.
  #
  # The result inherits any tainting in the original string or any supplied
  # replacement string.
  #
  #    "hello".gsub(/[aeiou]/, '*')              #=> "h*ll*"
  #    "hello".gsub(/([aeiou])/, '<\1>')         #=> "h<e>ll<o>"
  #    "hello".gsub(/./) {|s| s[0].to_s + ' '}   #=> "104 101 108 108 111 "
  #
  #
  def gsub(pattern, replacement)
    # This is just a stub for a builtin Ruby method.
    # See the top of this file for more info.
  end

 # If a string is used as the replacement, special variables from the match

  # (such as <code>$&</code> and <code>$1</code>) cannot be substituted into it,

  # as substitution into the string occurs before the pattern match

  # starts. However, the sequences <code>\1</code>, <code>\2</code>, and so on

  # may be used to interpolate successive groups in the match.

 # In the block form, the current match string is passed in as a parameter, and

  # variables such as <code>$1</code>, <code>$2</code>, <code>$`</code>,

  # <code>$&</code>, and <code>$’</code> will be set appropriately. The value

  # returned by the block will be substituted for the match on each call.

module ActiveSupport
  # The Inflector transforms words from singular to plural, class names to table names, modularized class names to ones without,
  # and class names to foreign keys. The default inflections for pluralization, singularization, and uncountable words are kept
  # in inflections.rb.
  #
  # The Rails core team has stated patches for the inflections library will not be accepted
  # in order to avoid breaking legacy applications which may be relying on errant inflections.
  # If you discover an incorrect inflection and require it for your application, you'll need
  # to correct it yourself (explained below).
  module Inflector
    extend self

    # By default, +camelize+ converts strings to UpperCamelCase. If the argument to +camelize+
    # is set to <tt>:lower</tt> then +camelize+ produces lowerCamelCase.
    #
    # +camelize+ will also convert '/' to '::' which is useful for converting paths to namespaces.
    #
    # Examples:
    #   "active_record".camelize                # => "ActiveRecord"
    #   "active_record".camelize(:lower)        # => "activeRecord"
    #   "active_record/errors".camelize         # => "ActiveRecord::Errors"
    #   "active_record/errors".camelize(:lower) # => "activeRecord::Errors"
    #
    # As a rule of thumb you can think of +camelize+ as the inverse of +underscore+,
    # though there are cases where that does not hold:
    #
    #   "SSLError".underscore.camelize # => "SslError"
    def camelize(lower_case_and_underscored_word, first_letter_in_uppercase = true)
      if first_letter_in_uppercase
        lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::#{$1.upcase}" }.gsub(/(?:^|_)(.)/) { $1.upcase }
      else
        lower_case_and_underscored_word.to_s[0].chr.downcase + camelize(lower_case_and_underscored_word)[1..-1]
      end
    end

    # Makes an underscored, lowercase form from the expression in the string.
    #
    # Changes '::' to '/' to convert namespaces to paths.
    #
    # Examples:
    #   "ActiveRecord".underscore         # => "active_record"
    #   "ActiveRecord::Errors".underscore # => active_record/errors
    #
    # As a rule of thumb you can think of +underscore+ as the inverse of +camelize+,
    # though there are cases where that does not hold:
    #
    #   "SSLError".underscore.camelize # => "SslError"
    def underscore(camel_cased_word)
      word = camel_cased_word.to_s.dup
      word.gsub!(/::/, '/')
      word.gsub!(/([A-Z]+)([A-Z][a-z])/,'\1_\2')
      word.gsub!(/([a-z\d])([A-Z])/,'\1_\2')
      word.tr!("-", "_")
      word.downcase!
      word
    end

    # Replaces underscores with dashes in the string.
    #
    # Example:
    #   "puni_puni" # => "puni-puni"
    def dasherize(underscored_word)
      underscored_word.gsub(/_/, '-')
    end

    # Removes the module part from the expression in the string.
    #
    # Examples:
    #   "ActiveRecord::CoreExtensions::String::Inflections".demodulize # => "Inflections"
    #   "Inflections".demodulize                                       # => "Inflections"
    def demodulize(class_name_in_module)
      class_name_in_module.to_s.gsub(/^.*::/, '')
    end

    # Creates a foreign key name from a class name.
    # +separate_class_name_and_id_with_underscore+ sets whether
    # the method should put '_' between the name and 'id'.
    #
    # Examples:
    #   "Message".foreign_key        # => "message_id"
    #   "Message".foreign_key(false) # => "messageid"
    #   "Admin::Post".foreign_key    # => "post_id"
    def foreign_key(class_name, separate_class_name_and_id_with_underscore = true)
      underscore(demodulize(class_name)) + (separate_class_name_and_id_with_underscore ? "_id" : "id")
    end

    # Ruby 1.9 introduces an inherit argument for Module#const_get and
    # #const_defined? and changes their default behavior.
    if Module.method(:const_get).arity == 1
      # Tries to find a constant with the name specified in the argument string:
      #
      #   "Module".constantize     # => Module
      #   "Test::Unit".constantize # => Test::Unit
      #
      # The name is assumed to be the one of a top-level constant, no matter whether
      # it starts with "::" or not. No lexical context is taken into account:
      #
      #   C = 'outside'
      #   module M
      #     C = 'inside'
      #     C               # => 'inside'
      #     "C".constantize # => 'outside', same as ::C
      #   end
      #
      # NameError is raised when the name is not in CamelCase or the constant is
      # unknown.
      def constantize(camel_cased_word)
        names = camel_cased_word.split('::')
        names.shift if names.empty? || names.first.empty?

        constant = Object
        names.each do |name|
          constant = constant.const_defined?(name) ? constant.const_get(name) : constant.const_missing(name)
        end
        constant
      end
    else
      def constantize(camel_cased_word) #:nodoc:
        names = camel_cased_word.split('::')
        names.shift if names.empty? || names.first.empty?

        constant = Object
        names.each do |name|
          constant = constant.const_defined?(name, false) ? constant.const_get(name) : constant.const_missing(name)
        end
        constant
      end
    end

    # Turns a number into an ordinal string used to denote the position in an
    # ordered sequence such as 1st, 2nd, 3rd, 4th.
    #
    # Examples:
    #   ordinalize(1)     # => "1st"
    #   ordinalize(2)     # => "2nd"
    #   ordinalize(1002)  # => "1002nd"
    #   ordinalize(1003)  # => "1003rd"
    def ordinalize(number)
      if (11..13).include?(number.to_i % 100)
        "#{number}th"
      else
        case number.to_i % 10
          when 1; "#{number}st"
          when 2; "#{number}nd"
          when 3; "#{number}rd"
          else    "#{number}th"
        end
      end
    end
  end
end

module A
module B
extend self
.....
end
end

module Foo
  module Bar
      extend self # self => Foo::Bar

    def hello
      p "hello"
    end
  end
end

class Klass
  include Foo::Bar
end

Klass.new.hello #  "hello"
Foo::Bar.hello # "hello"
Klass.hello # undefined method `hello' for Klass:Class (NoMethodError)

module A
def self.foo
end
end

module A
extend self
def foo
end
end

module Foo
  module Bar     

    def hello
      p "hello"
    end
  end
end

class Klass
  include Foo::Bar
end

Foo::Bar.extend(Foo::Bar)

Klass.new.hello #  "hello"
Foo::Bar.hello # "hello"
Klass.hello # undefined method `hello' for Klass:Class (NoMethodError)