From: David Masover <ninja@...>
Date: 2011-06-10T17:34:24+09:00
Subject: Re: CORE - Literal Instantiation breaks Object Model

On Thursday, June 09, 2011 05:30:43 PM Yukihiro Matsumoto wrote:
> |The questions are:
> |
> |b) Is there any way to track (intercept) the instantiation of objects
> |(especially those instantiated from literals)
> |
> |  1) without a C-level extension
> |  2) with a C-level extension
> 
> If you don't care about performance, you can investigate
> ObjectSpace#each_object.  Note that JRuby turns off the method by
> default for performance reason.  If you care about performance, I am
> afraid that you have to modify the interpreter itself.

Even this has limitations.
A few things that aren't in ObjectSpace:

Fixnum (but note, Bignum _is_ there)
Symbol
TrueClass
FalseClass
NilClass

That's just off the top of my head.

But I guess that's the best we can do when entirely guessing at Ilias' actual 
goal -- as we must do every time he posts. The best we have is:

> Ability to track instantiation of every object within the system.

If he wants to track instantiation for performance reasons -- for example, to 
see how many objects he's using at a given moment -- then ObjectSpace might 
work, just slowly. If there's some reason he wants to know when a Fixnum is 
"created", then ObjectSpace isn't sufficient, and I imagine a C extension is 
the least that's required.