From: Lazaridis Ilias <ilias@...>
Date: 2011-07-01T14:12:24+09:00
Subject: [ruby-core:37712] [Ruby 1.9 - Bug #4893] Literal Instantiation breaks Object Model


Issue #4893 has been updated by Lazaridis Ilias.


Yukihiro Matsumoto wrote:
> Introducing a new global status is a very bad idea.  It doesn't work well with threads.  

All threads share the same (global) instance of the String class object, thus the flag "call_initialize" is naturally global. 

> Besides that, it makes program behavior more complex and less understandable.  

I've described the final implementation, which makes "call_initialize" an internal implementation detail, completely hidden from the user.

Currently, I wanted a confirmation that the patch works *technically*, thus I can go on to the next step  (= incremental design/implementation).

> It's not acceptable for new addition.

Why do you place the issue again on "reject", instead of awaiting the final implementation?



----------------------------------------
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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