From: Yukihiro Matsumoto <matz@...>
Date: 2011-07-06T17:18:00+09:00
Subject: [ruby-core:37823] [Ruby 1.9 - Bug #4893] Literal Instantiation breaks Object Model


Issue #4893 has been updated by Yukihiro Matsumoto.


|VARIABLE:
|* I don't use *any* global variable (but an internal class-object scope variable)
|* I use the same (string-)class-object scope flags that are used *excessively* within the existent ruby source-codes.

OK, you don't use the C global variable any longer.  But still uses
global status, that I mean a line of 

  String.call_initialize=true

in anywhere in the program can change the whole behavior of whole
program so much.  Comparing to other usage of global statuses (some of
which I regret), influence of this change is too huge.

|At this point, if you still have objections, I ask you friendly to demonstrate them with test-code. This issue is far to deep to be handled with words.

Did you measured the performance?

							matz.

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