[#48745] [ruby-trunk - Bug #7267][Open] Dir.glob on Mac OS X returns unexpected string encodings for unicode file names — "kennygrant (Kenny Grant)" <kennygrant@...>

17 messages 2012/11/02

[#48773] [ruby-trunk - Bug #7269][Open] Refinement doesn't work if using locate after method — "ko1 (Koichi Sasada)" <redmine@...>

12 messages 2012/11/03

[#48847] [ruby-trunk - Bug #7274][Open] UnboundMethods should be bindable to any object that is_a?(owner of the UnboundMethod) — "rits (First Last)" <redmine@...>

21 messages 2012/11/04

[#48854] [ruby-trunk - Bug #7276][Open] TestFile#test_utime failure — "jonforums (Jon Forums)" <redmine@...>

14 messages 2012/11/04

[#48988] [ruby-trunk - Feature #7292][Open] Enumerable#to_h — "marcandre (Marc-Andre Lafortune)" <ruby-core@...>

40 messages 2012/11/06

[#48997] [ruby-trunk - Feature #7297][Open] map_to alias for each_with_object — "nathan.f77 (Nathan Broadbent)" <nathan.f77@...>

19 messages 2012/11/06

[#49001] [ruby-trunk - Bug #7298][Open] Behavior of Enumerator.new different between 1.9.3 and 2.0.0 — "ayumin (Ayumu AIZAWA)" <ayumu.aizawa@...>

12 messages 2012/11/06

[#49018] [ruby-trunk - Feature #7299][Open] Ruby should not completely ignore blocks. — "marcandre (Marc-Andre Lafortune)" <ruby-core@...>

13 messages 2012/11/07

[#49044] [ruby-trunk - Bug #7304][Open] Random test failures around test_autoclose_true_closed_by_finalizer — "luislavena (Luis Lavena)" <luislavena@...>

11 messages 2012/11/07

[#49196] [ruby-trunk - Feature #7322][Open] Add a new operator name #>< for bit-wise "exclusive or" — "alexeymuranov (Alexey Muranov)" <redmine@...>

18 messages 2012/11/10

[#49211] [ruby-trunk - Feature #7328][Open] Move ** operator precedence under unary + and - — "boris_stitnicky (Boris Stitnicky)" <boris@...>

20 messages 2012/11/11

[#49229] [ruby-trunk - Bug #7331][Open] Set the precedence of unary `-` equal to the precedence `-`, same for `+` — "alexeymuranov (Alexey Muranov)" <redmine@...>

17 messages 2012/11/11

[#49256] [ruby-trunk - Feature #7336][Open] Flexiable OPerator Precedence — "trans (Thomas Sawyer)" <transfire@...>

18 messages 2012/11/12

[#49354] review open pull requests on github — Zachary Scott <zachary@...>

Could we get a review on any open pull requests on github before the

12 messages 2012/11/15
[#49355] Re: review open pull requests on github — "NARUSE, Yui" <naruse@...> 2012/11/15

2012/11/15 Zachary Scott <[email protected]>:

[#49356] Re: review open pull requests on github — Zachary Scott <zachary@...> 2012/11/15

Ok, I was hoping one of the maintainers might want to.

[#49451] [ruby-trunk - Bug #7374][Open] File.expand_path resolving to first file/dir instead of absolute path — mdube@... (Martin Dubé) <mdube@...>

12 messages 2012/11/16

[#49463] [ruby-trunk - Feature #7375][Open] embedding libyaml in psych for Ruby 2.0 — "tenderlovemaking (Aaron Patterson)" <aaron@...>

21 messages 2012/11/16
[#49494] [ruby-trunk - Feature #7375] embedding libyaml in psych for Ruby 2.0 — "vo.x (Vit Ondruch)" <v.ondruch@...> 2012/11/17

[#49467] [ruby-trunk - Feature #7377][Open] #indetical? as an alias for #equal? — "aef (Alexander E. Fischer)" <aef@...>

13 messages 2012/11/17

[#49558] [ruby-trunk - Bug #7395][Open] Negative numbers can't be primes by definition — "zzak (Zachary Scott)" <zachary@...>

10 messages 2012/11/19

[#49566] [ruby-trunk - Feature #7400][Open] Incorporate OpenSSL tests from JRuby. — "zzak (Zachary Scott)" <zachary@...>

11 messages 2012/11/19

[#49770] [ruby-trunk - Feature #7414][Open] Now that const_get supports "Foo::Bar" syntax, so should const_defined?. — "robertgleeson (Robert Gleeson)" <rob@...>

9 messages 2012/11/20

[#49950] [ruby-trunk - Feature #7427][Assigned] Update Rubygems — "mame (Yusuke Endoh)" <mame@...>

17 messages 2012/11/24

[#50043] [ruby-trunk - Bug #7429][Open] Provide options for core collections to customize behavior — "headius (Charles Nutter)" <headius@...>

10 messages 2012/11/24

[#50092] [ruby-trunk - Feature #7434][Open] Allow caller_locations and backtrace_locations to receive negative params — "sam.saffron (Sam Saffron)" <sam.saffron@...>

21 messages 2012/11/25

[#50094] [ruby-trunk - Bug #7436][Open] Allow for a "granularity" flag for backtrace_locations — "sam.saffron (Sam Saffron)" <sam.saffron@...>

11 messages 2012/11/25

[#50207] [ruby-trunk - Bug #7445][Open] strptime('%s %z') doesn't work — "felipec (Felipe Contreras)" <felipe.contreras@...>

19 messages 2012/11/27

[#50424] [ruby-trunk - Bug #7485][Open] ruby cannot build on mingw32 due to missing __sync_val_compare_and_swap — "drbrain (Eric Hodel)" <[email protected]>

15 messages 2012/11/30

[#50429] [ruby-trunk - Feature #7487][Open] Cutting through the issues with Refinements — "trans (Thomas Sawyer)" <transfire@...>

13 messages 2012/11/30

[ruby-core:49968] [ruby-trunk - Feature #6682][Assigned] Add a method to return an instance attached by a singleton class

From: "mame (Yusuke Endoh)" <mame@...>
Date: 2012-11-24 02:12:54 UTC
List: ruby-core #49968
Issue #6682 has been updated by mame (Yusuke Endoh).

Status changed from Open to Assigned
Target version set to next minor


----------------------------------------
Feature #6682: Add a method to return an instance attached by a singleton class
https://bugs.ruby-lang.org/issues/6682#change-33734

Author: ryoqun (Ryo Onodera)
Status: Assigned
Priority: Normal
Assignee: shyouhei (Shyouhei Urabe)
Category: core
Target version: next minor


=begin
Currently, there is no easy way to get the attached instance from a singleton class. For MRI, we have to resort to writing an C extension. So it'll be useful to add an instance method to Class to return the attached instance if the given class object is a singleton class.

I'll show what I want in the code-wise with the following code snippet:

  text = "I love Ruby."
  klass = text.singleton_class
  # => #<Class:#<String:0x000000027383e8>>
  
  klass.singleton_instance # <= This is the new method.
  # => "I love Ruby."
  
  String.singleton_instance # <= This should return nil because String isn't a singleton class and there is no singleton instance, rather there will be many instances.
  # => nil

As for use cases, in my case, I wanted to create a module to add class methods. And it has some state, so must be initialized properly. And it can equally be used by Class#extend and Class#include like this:

  module Countable
    attr_reader(:count)
  
    class << self
      def extended(extended_class)
        p("extending #{extended_class}")
        super
  
        initialize_state(extended_class)
      end
  
      def included(included_class)
        p("including #{included_class}")
        super
  
        if included_class.singleton_instance # <= Currently, I can't do this.
          initialize_state(included_class.singleton_instance)
        end
      end
  
      private
      def initialize_state(object)
        p("initializing state of #{object}")
        object.instance_variable_set(:@count, 0)
      end
    end
  end
  
  class Person
    extend(Countable)
  end
  
  class Book
    class << self
      include(Countable)
    end
  end
  
  p(Person.count)
  p(Book.count)
  
  # => "extending Person"
  # => "initializing state of Person"
  # => "including #<Class:Book>"
  # => "initializing state of Book"
  # => 0
  # => 0

Others wanted this functionality as shown by ((<this stackoverflow page|URL:http://stackoverflow.com/questions/7053455/given-a-ruby-metaclass-how-do-i-get-the-instance-to-which-it-is-attached>)). Also, I found several actual C-extensions for this kind of functionality on the wild browsing ((<a search result|URL:https://github.com/search?q=rb_iv_get+__attached__&repo=&langOverride=&start_value=1&type=Code&language=C>)) on github.

* ((<eigen|URL:https://github.com/elliottcable/refinery/blob/853dcc2254557200d1d6be4cb9c105e8fa9d01a9/ext/eigen/eigen.c#L12>))
* ((<mult|URL:https://github.com/banister/mult/blob/6a1d0bdd383e7e231c5b7c2c718204dfb6ba28ca/ext/mult/mult.c#L43>))

Thanks for creating a great language. Especially I love its meta-programming capability. I'd wish this feature to lead to better meta-programming capability of Ruby.
=end



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