From: Lazaridis Ilias <ilias@...>
Date: 2011-07-04T21:02:16+09:00
Subject: [ruby-core:37768] [Ruby 1.9 - Bug #4893] Literal Instantiation breaks Object Model


Issue #4893 has been updated by Lazaridis Ilias.

File String_call_initialize_v3.diff added

Find attached a patch which removes the translation-unit-visible "static int call_initialize" flag, and introduces the low-level flag "FL_USER18" of the String class object. 

There was no documentation about those flags. "FL_USER18" seemed unused, please let me know if I should use another one.

Lazaridis Ilias wrote:
[...]
> * is there a standard mechanism to detect "singleton-method created/deleted", which works on the C-level?

I've found the "(singleton_)method_added/removed/undefined group of call-backs, those should be usable to implement the last step (automated activation/deactivation of the flag).

-


----------------------------------------
Bug #4893: Literal Instantiation breaks Object Model
http://redmine.ruby-lang.org/issues/4893

Author: Lazaridis Ilias
Status: Rejected
Priority: Normal
Assignee: Yukihiro Matsumoto
Category: 
Target version: 
ruby -v: 1.9.2


#String2.rb 
class String 
  def initialize(val) 
    self.replace(val) 
    puts object_id 
  end 
  def my_method_test 
    'has method <my_method_test>' 
  end 
end 

# command line 
$ irb 
irb(main):001:0> original = String.new("original") 
=> "original" 
irb(main):002:0> load "String2.rb" 
=> true 
irb(main):003:0> altered = String.new("altered") 
21878604 
=> "altered" 
irb(main):004:0> altered.my_method_test 
=> "has method <my_method_test>" 
irb(main):005:0> literal = "literal" 
=> "literal" 
irb(main):006:0> literal.my_method_test 
=> "has method <my_method_test>" 
irb(main):007:0> 

- 

The initialize method is an integral part of the class String. 
From the moment that "String2.rb" is loaded, the initialize method of 
class String has been validly redefined. 

(The behaviour of the String class within the "irb session" is 
altered) 

The altered initialize method is now an integral part of the class 
String. 

The altered String object behaves as expected (responds to 
"my_method_test, initialized via redefined initialize method). 

The String(Literal) object responds to "my_method_test", but it is was 
not initialized with the redefined initialize method. 

- 

The "Literal Instantiation" calls the original (core-C-level) String 
initialize method instead of the redefined one (user-language-level). 
This *breaks* the object model. 





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